PLACE IN RETURN BOX to remove this checkout from your record.
To AVOID FINES return on or before date due.
MAY BE RECALLED with earlier due date if requested.

 

DATE DUE DATE DUE DATE DUE

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

5’08 KlProyWra-ICIR ClDateDueJndd

 

 

ANALYSIS OF MULTIPLE INSTRUCTIONAL TECHNIQUES ON THE
UNDERSTANDING
AND RETENTION OF SELECT MECHANICS TOPICS
By

Sara Elizabeth Fetsco

A THESIS

Submitted to
Michigan State University
in partial fulfillment of the requirements
for the degree Of

MASTER OF SCIENCE
Interdepartmental Physical Science

2010

ABSTRACT
ANALYSIS OF MULTIPLE INSTRUCTIONAL TECHNIQUES ON THE
UNDERSTANDING
AND RETENTION OF SELECT MECHANICS TOPICS
By
Sara Elizabeth Fetsco
There are several topics that introductory physics students typically have
difficulty understanding. The purpose of this thesis is to investigate if multiple
instructional techniques will help students to better understand and retain the material.
The three units analyzed in this study are graphing motion, projectile motion, and
conservation of momentum. For each unit students were taught using new or altered
instructional methods including online laboratory simulations, inquiry labs, and
interactive demonstrations. Additionally, traditional instructional methods such as
lecture and problem sets were retained. Effectiveness was measured through pre- and
post-tests and student opinion surveys. Results suggest that incorporating multiple
instructional techniques into teaching will improve student understanding and retention.

Students stated that they learned well from all of the instructional methods used except

the online simulations.

ACKNOWLEDGEMENTS

I am grateful to Merle Heidemann and Ken Nadler for their guidance and support

throughout the writing Of this thesis.

TABLE OF CONTENTS

LIST OF TABLES ..................................................................................... v

LIST OF FIGURES ................................................................................... vi
INTRODUCTION .................................................................................... 1

Rationale ...................................................................................... 1

Literature ...................................................................................... 3

Summary of Overarching Ideas ............................................................ 7

Demographics ................................................................................ 9

IMPLEMENTATION .............................................................................. 1 1

Overview of Units .......................................................................... 15

Unit One: Graphing Motion ...................................................... 15

Unit Two: Projectile Motion ..................................................... 18

Unit Three: Conservation of Momentum ....................................... 20

Student Surveys ................................................................... 22

Final Exam ......................................................................... 22

RESULTS/DISCUSSION ......................................................................... 24

Unit One: Graphing Motion ............................................................... 24

Unit Two: Projectile Motion .............................................................. 32

Unit Three: Conservation of Momentum ................................................ 38

Student Survey Results .................................................................... 46

Retention of Knowledge Over Time ..................................................... 47
CONCLUSION .................................................................................... 50

Unit One: Graphing Motion ............................................................... 50

Unit Two: Projectile Motion .............................................................. 52

Unit Three: Conservation of Momentum ................................................ 54

Overall ....................................................................................... 56

APPENDICES ....................................................................................... 59

BIBLIOGRAPHY ................................................................................. 1 52

LIST OF TABLES

Table 1: Graphing Motion Unit Outline .......................................................... 12
Table 2: Projectile Motion Unit Outline ......................................................... 13
Table 3: Conservation of Momentum Unit Outline ...................................................... 14
Table 4: Scoring Rubric for Graphing Motion Tests .................................................... 140
Table 5: Scoring Rubric for Projectile Motion Tests ................................................... 141
Table 6: Scoring Rubric for Conservation Of Momentum Tests ....................................... 142
Table 7: Graphing Motion Pre/Post-Test Paired Questions ............................................ 147
Table 8: Projectile Motion Pre/Post-Test Paired Questions ........................................... 148
Table 9: Conservation Of Momentum Pre/Post-Test Paired Questions .............................. 149

LIST OF FIGURES

Figure 1: Moving Man Simulation ................................................................ 16
Figure 2: Projectile Motion Simulation .................................................................. 19

Figure 3: Conservation of Momentum Simulation ...................................................... 21

Figure 4: Graph of Objective A Pre/Post-test Results .................................................... 26
Figure 5: Graph of Objective B Pre/Post-test Results ................................................... 28
Figure 6: Graph Of Objective C Pre/Post-test Results ................................................... 29
Figure 7: Graph Of Objective D Pre/Post-test Results ................................................... 31
Figure 8: Graph of Objective E Pre/Post-test Results .................................................... 33
Figure 9: Graph of Objective F Pre/Post-test Results .................................................... 35
Figure 10: Graph of Objective G Pre/Post-test Results .................................................. 37
Figure 11: Graph of Objective H and I Pre/Post-test Results ........................................... 40
Figure 12: Graph of Objective J Pre/Post-test Results ................................................... 42
Figure 13: Graph of Objective K Pre/Post-test Results .................................................. 43
Figure 14: Graph of Objective L Pre/Post-test Results ................................................... 45
Figure 15: Graph Of Student Survey Results .............................................................. 46
Figure 16: Graph of Final Exam vs. Post-test Scores .................................................... 48

vi

Introduction

Rationale:

The subject Of physics is typically considered by high school students to be
difficult. This is due to many reasons. First, physics is mathematically demanding,
requiring a solid understanding Of Algebra 2. Second, students are challenged to think in
ways that are different than what they have always done in past science classes; they are
asked to combine science and math into one united subject. Third, they are continually
asked to revise long held ideas about the physical world Of which they have many
contradictory Observations. For example, most students will tell you that heavy Objects
fall faster than lighter ones, and unquestioningly believe this until repeatedly challenged.
In addition, most students, when confronted with data different than what they believe it
should be in a lab, will ignore, reject, exclude, or misinterpret, generally making only
minor conceptual changes (Hynd 1995). After teaching physics at the high school level
for three years, I have pinpointed three topics that students particularly have trouble
understanding in relation to mechanics: projectile motion, graphing motion, and
conservation Of momentum. These three units could be improved by the addition Of more

focused laboratory experiences and other hands-on activities.

In our curriculum, the first topic taught is vectors and the second is straight line
motion. Graphing motion is usually taught a day after straight line motion

(displacement, velocity, and acceleration) has been presented. This topic occupies about

two days of class time, and is included in the one-dimensional motion unit test.
Typically, I give a short lecture, followed by a class demonstration using the motion
detector. Then, students will complete a worksheet in which they plot points and graph
position, velocity, and acceleration. They also complete several book problems. Often,
students look at the graphs as if they are snapshots of motion, instead Of viewing them as
a representation Of motion over time. Beichner (1996) found that in addition to a
“photographic-like” representation, students become confused with the slope/height Of

graphs as well as the meaning of the area under graphs.

Projectile motion follows immediately after one dimensional motion. The unit
involves a lecture, several demonstrations, and a lab using projectile launchers. Usually,
students are quite proficient at analyzing horizontally launched projectiles. However,
projectiles launched at an angle to the ground prove much more difficult to conceptualize,
as does the concept of independent horizontal and vertical components. While students
can repeat this fact for me, they cannot correctly answer related questions. They also
struggle to solve mathematical problems in which they need to alternate between using

horizontal and vertical components.

Finally, conservation of momentum typically ends up being the last unit of the
trimester, following energy and circular motion. I find that the concept of transfer of
momentum is difficult. Students struggle with drawing and then translating their
diagrams into equations they can solve. Usually, examples of momentum are done with
demonstrations, but we do not use actual velocities in solving the related problems.

Students are simply asked to Observe a decrease or increase in the velocity afier collision.

They are also asked to solve conservation of momentum problems mathematically, and,
in this particular area, students tend to get confused with positive and negative directions.

There are not any labs in this unit.

My hypothesis is that using multiple instructional techniques will improve student
understanding and retention of these three topics. These techniques include online
simulations, labs that are more focused, and demonstrations that aptly display the
concept. The traditional instruction I have used in years past such as lectures and

problem sets will be retained.

Literature

There has been much research done (eg. Akpan, Beichner, Finkelstein, Lunetta) in the
way of microcomputer based labs (MBL), or, simulations, in the classroom. Three
characteristics of a simulation are:

1. It represents a real situation.

2. It provides user control over the problem/situation.

3. It omits certain distracting variables that are irrelevant or unimportant such as

friction (Lunetta & Hofstein 1981).

Physics simulations are readily available online, but have yet to be embraced fully by
teachers. The main reasons for this are: lack of prep time, quality of simulations, and the
fact that teachers must change the way they teach to implement them (Foti & Ring 2008).

The advantages of simulations are that they use less class time than labs and that they can

even be completed and/or repeated by students at home (Choi & Gennaro 1987).
Additionally, most online Simulations are open source, whereas the lab supplies to
perform these same experiments can be quite costly. However, students do lose the
manipulative skills that they would learn executing an actual lab exercise (Hofstein &
Lunetta 1982), so it is very important that simulations are not simply substituted for real
lab activities. Studies have been done that indicate that simulations, when designed
properly and used in the right context, can be as effective or even more effective than
using real lab equipment (F inkelstein et al 2005). This study by Finkelstein showed that
students who worked with physical circuit elements did worse on assessments than those
who used an online Simulation, even when that assessment involved building real circuits.
The researchers attributed some Of this disparity to the fact that simulations work to focus
a student’s attention on the important aspects and minimize distractions caused by
equipment. An important factor to consider with simulations is whether or not the
concept can be effectively Shown in another way, or even more effectively shown in a lab
setting or demonstration. Situations in which Simulations are better alternatives are when
there may be a lack Of equipment available due to expense or limited resources, a history
Of inaccurate or contradictory results, or data collecting software/hardware reliability. It
has also been found that using a simulation prior to formal instruction on a topic resulted
in much higher achievement compared to formal instruction followed by simulation use
(Brant, Hooper, & Sugrue 1991). Akpan also confirmed the “Sim first” theory by noting
that groups who performed a virtual dissection before performing an actual dissection did
much better on short answer questions than groups who did the actual dissection,

followed by the virtual dissection (Akpan 2001). Taking into account the results of these

4

findings, I made every effort to assign the Simulations I chose before I presented a topic

in class.

The typical high school laboratory setting requires students to have a thorough
knowledge of different measuring techniques. Students are asked to measure distances
and times, determine masses and volumes, as well as read temperature, and then perform
various calculations. 40-60% of time used during a traditional lab is in taking
measurements (Hucke & Fischer 2002). While the skills involved in measurement taking
are important skills to have, when the amount of time spent become excessive, one has to
ask whether other aspects, such as the concept of the lab, are left behind. Measurement
time can be greatly decreased by adding probe-ware into the lab, which many secondary
science classrooms have if money is available. In my classroom, we do have the probes
available and use them to a certain extent. Computer-based data capture and processing
can be very useful. The main advantage is the ability Of students to immediately analyze
data, which the computer conveniently converts into a graph or chart of some sort,
depending on the program used. In Hucke & Fisher’s study (2002), only 5% of lab time

was used for computer-specific activities such as saving and formatting graphs .

Another aspect Of labs that is frequently discussed is the “cookbook” lab vs. the
inquiry based lab. Cookbook labs usually have a list of steps for students to follow in
order to arrive at a prescribed ending, and most students will be able to tell if they got the
“right answer” or not. Fully inquiry based labs are much more open-ended. There is not
one right way to do the lab, and students are left to brainstorm protocols and solutions on

their own. The benefit of inquiry labs is that students learn more when doing these than

when working through step-by-step directions; they also have enhanced science attitudes,
reasoning skills, and better retention (Lord & Orkwisnewski 2006). However, there are
some downsides to inquiry because they increase student frustration levels, they take
longer to complete because students take time to come up with a feasible procedure, and
there is less teacher control (Deters 2005). In addition, while inquiry labs are more likely
to produce conceptual learning as compared to cookbook labs, students often find them
less satisfying. Cookbook labs are definitely preferred among students, especially among
the lower achieving students (Royuk & Brooks 2003). The labs I currently use are a
mixture of inquiry-based and cookbook labs. To maximize the benefits of both types for
this study, I used lab activity formals that take the best of both worlds: enough guidance

for students to feel satisfied, but with inquiry aspects to the lab.

A classroom demonstration is typically when a teacher performs an experiment
while the students Observe and take notes. Usually the demonstration involves expensive
equipment, limited supplies, or dangerous materials, prompting the demonstration in the
first place (Milne & Oteino 2007). However, there has been some criticism of
demonstrations as a teaching tOOl (Roth et a1 1997 and Lynch & Zonchak 2002).
Demonstrations are not hands-on and limit student inquiry when done in the traditional
way. Sometimes they are also poorly integrated into the curriculum and therefore
become more of a hindrance to learning than a help (Roth & Lucas 1997). In other words,
demonstrations may bog down curriculum and do little to advance student knowledge.

In order to meet the expectations that most teachers have for demonstrations, such as
increasing student understanding, the demonstrations need to have specific structure to

them as opposed to a “Show and tell” atmosphere (Shepardson et al 1994). This specific
6

structure includes built-in questions and discussion time, almost making it a class inquiry
project as Opposed to simply explaining how or why something occurs. Roth (1997)
suggests some guidelines to follow:
1. Time for student discussion with their classmates in order to share and verify
what they Observed and understood.
2. Time for teachers to check student understanding for a correct explanation of
what happened.
3. Engagement of students to talk about the demonstration.
Using these guidelines, a rich environment can be created where students can engage in

many types of activities related to the demonstration.

Summary of Overarching Ideas

Graphing motion deals with three graphs: distance vs. time, velocity vs. time, and
acceleration vs. time. The slope of a distance vs. time graph yields the velocity, and the
slope of a velocity vs. time graph yields acceleration. Conversely, taking the area under
an acceleration vs. time graph yields velocity and the area under a velocity vs. time graph
yields distance. Using these guidelines, nearly any graph Of motion can be analyzed to

obtain a detailed description of the motion that is being represented.

Projectile motion in introductory physics deals with two dimensions only,
horizontal and vertical. The central idea to remember in solving these problems is that
the two components are independent of each other. It does not make any difference how

large the horizontal velocity is because it does not affect the vertical velocity in any way.

7

However, time does link these two components together, which proves useful when
solving quantitative problems of this nature. The horizontal velocity of a projectile is
constant (when disregarding air resistance) because there is no acceleration. The vertical
velocity of a projectile will change because Of the acceleration due to gravity. Since the
two components are independent of each other, solving projectile motion problems is like
solving two problems: a free fall problem and a horizontal motion problem, with one
variable, time, shared between the two. I have found that a major misconception among
my students is that an Object with a horizontal velocity will take longer to fall to the

ground than an Object that is simply dropped from the same height.

Momentum is the product of mass and velocity. In everyday language,
momentum and inertia are used interchangeably, when in reality they are not the same
thing. Inertia is an intrinsic property of an object, and is actually just the amount of mass
in an Object. For example, a bullet has little inertia, but a lot of momentum. The
impulse-momentum theory states that the force multiplied by the change in time is equal
to the change in momentum. This is the reason that we have airbags in cars: increasing
the amount of time the airbag is in contact with the object decreases the force applied to
the Object. In a closed system, momentum is always conserved. Conservation of
momentum can be applied to any closed system, commonly collisions. There are two
general types of collisions: elastic and inelastic. Elastic collisions are ones in which the
Objects bounce off each other, and inelastic collisions are when the Objects collide and

stick together, moving with a common velocity.

Demographics

The research for this project was completed at Seaholm High School in
Birmingham, MI. Birmingham is a suburban, middle to upper class city located in metro
Detroit. The city of Birmingham website (Vision 2010) indicates that at least 38% Of the
over-25 population has a bachelor’s degree and a further 30% of the population over age
25 has a graduate degree of some sort. The median household income is just over
$100,000, and the poverty is less than 3%. According to the 2000 census, Birmingham
has a population of over 19,000, 97.1% of those are white, 1.1% African American, and

2.0% Asian. (Birmingham, 2010)

The school district is made up of eight elementary schools, two middle schools,

two high schools, a 3rd -8th grade school for students and parents who choose this unique

program, and an alternative high school program. According to district documents
(Board 2009), the graduation rate is 94.53%, and only 3.13% of students qualify for free
or reduced lunch. Seaholm High School itself is made up of around 1300 students. 90.3
% are Caucasian, 3.4% are African American, 1.6 % are Asian, 1.8% are Hispanic, and
2.8% are “other”. In contrast, the other high school in the district, Groves, is made up of
77% Caucasian and 19% African American. The school is on a trimester schedule, and
this study was conducted the third year after implementation of the trimester schedule.
Trimesters have been hard for teachers and students alike to adjust to. Both groups feel
rushed completing an entire semester’s worth of material in 12 weeks. As a result, most
Advanced Placement classes and lower level classes are three trimesters in length, in an

effort to provide more time for students to comprehend the material. There is a

9

pronounced lack of enthusiasm for trimester from a large majority of the school
population. With the addition of the new Michigan Content Expectations the same year
we began trimester, our science department had to make some tough decisions in the
classroom when it came to labs and projects we had done in the past. Two labs were
eliminated from the first trimester physics course, and a project/competition the students
loved in which they constructed projectile launchers of their own design in groups- the
epitome of inquiry based leaming- was out also. These were some Of the reasons that I
decided to work on finding some more focused labs and Simulations, which take less
class time. The expectation is that these will leave room to bring back some of the things

that have been cut out due to time constraints.

This study was conducted on two sections of first trimester Physics A students
(mechanics). These students are either taking Algebra 2 concurrently, or have already
completed it. The classes are composed Of both juniors and seniors. A total of 25 out Of
40 students agreed to participate in the study by returning their signed consent form. The
school district also offers an honors and an advanced placement physics course, so the
sections studied are composed primarily of students who are of average ability in science

and math, most Of whom do not plan to study any subject related to physics in college.

10

Implementation

The unit outline below lists in chronological order the assignments that were given during
the period of this study. Additionally, appendix references are listed next to each
assignment as well as the type Of activity and the Objectives covered. Items in italics
have been developed or modified specifically for this study. For a list of Objectives, see

Appendix A.

11

Unit Outline

 

Unit One: Graphin Motion 9 days

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Assignment Name Appendix Type of Activity Objective(s)
Addressed
Straight Line Motion - Discussion -
Lecture
Problem set #1 - Homework -
(bookwork)
Graphing Motion B 1 Assessment A,B,C,D
Pre-test
Moving Man C1 Simulation A,B,C,D
Simulation
Graphing Motion C2 Discussion A,B,C,D
Lecture
Graphing Motion C3 Demonstration A,B,C
Demonstration
Motion in a Straight - Homework A,B,C,D
Line worksheet
Problem set #2 - Homework A,B,C,D
(bookwork)
Graphing Motion C4 Homework A,B,C
worksheet
Graphing Motion Lab C5 Lab A,B,C,D
Translation in - Homework A,B,C,D
Transylvania
worksheet
Quiz #1 - Assessment -
Free Fall Lecture - Discussion -
Problem set #3 - Homework -
(bookwork)
Free Fall lab - Lab -
Graphing Motion B2 Assessment A,B,C,D
Post-test

 

 

 

 

Table l: Graphing Motion Unit Outline

12

 

 

Unit Two: Projectile Motion 5 days

 

 

 

 

 

 

 

 

 

 

Assignment Name Appendix Type of Activity Objective(s)
Addressed
Projectile Motion B3 Assessment E,F,G
Pre-test
Projectile Motion C6 Simulation E,F
Simulation
Projectile Motion C7 Discussion E,F,G
Lecture
Projectile Motion C8 Demonstration E,G
Demonstrations
Problem set #4 - Homework F ,G
(bookwork)
Projectile Problems C9 Homework F ,G
worksheet
Projectile Motion C10 Lab E,F,G
Lab
Projectile Motion B4 Assessment E,F,G
Post-test

 

 

 

 

Table 2: Projectile Motion Unit Outline

13

 

 

Unit Three: Conservation of Momentum

7 days

 

 

 

 

 

 

 

 

 

 

 

 

 

Assignment Name Appendix Type of Activity Objective(s)
Addressed
Conservation of BS Assessment H,I,J,K,L
Momentum Pre-test
Conservation of C11 Simulation H,I,K
Momentum simulation
Momentum and - Discussion H,I,L
Impulse Lecture
Problem Set #5 - Homework H,I
(bookwork)
Problem Set #6 - Homework H,I
(bookwork)
Conservation of C12 Discussion H,I,J,K,L
Momentum Lecture
Conservation of C13 Demonstration I,J,K
Momentum
Demonstrations
Problem Set #7 - Homework H,I,J,K
(bookwork)
Momentum and Its - Homework H,I,J,K
Conservation
worksheet
Conservation of C14 Lab H,I,K
Momentum Lab
Momentum Post-test B6 Assessment H,I,J,K,L

 

 

 

 

 

Table 3: Conservation Of Momentum Unit Outline

As research shows, changes to teaching such as assigning simulations before labs,
presenting demonstrations that are more interactive, and using inquiry based labs will
improve student understanding and comprehension. Therefore, during the period of time
this study was conducted, simulation assignments were always collected before the lab
was conducted. Additionally, demonstrations were adapted to conform to the research-

based effective techniques and labs were altered to be more inquiry driven.

14

Pre-tests (Appendix B1,B3,B5) were given before any item in the unit was taught.
Students were not allowed to see the pre-tests at any time after they were collected. Pre-
test and posttest questions (Appendix B2,B4,B6) were closely related in order to
accurately gauge student comprehension after the concepts were taught. Whenever
possible, questions were identical between pre and post test. Simulations (Appendix
C1,C6,C11) were assigned to students and their responses were collected before they

began the actual lab in that unit.

Overview of Units
Unit One: Graphing Motion

The unit was begun by giving students the Graphing Motion Pre-test (Appendix
Bl) . Previous to this, the concepts of displacement, velocity, and acceleration were

discussed without graphing anything. The pre-test focused on two concepts:

a. Can students look at a graph and explain what is happening to displacement,

velocity, and acceleration, and vice versa?
b. Can students graph motion, given a description in words?

Over one weekend, students were also given an online Simulation assignment to complete
called “The Moving Man” (Appendix C1). This simulation came from the University of
Colorado at Boulder website, called PhET (2010). The simulation is of a person whose

motion can be controlled either by manually clicking and dragging him with the mouse,

15

or by inputting set values. The simulation features three graphs: displacement, velocity,

and acceleration Situated one on top of the other as pictured in Figure l.

 

Lg, The Moving Man (127)
PM Mid POM"! H019

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

‘7
when ”,th
l
v = 0.00 ’;l
o- —————————————— +— —————————————————
l no“ l :1:- j I— 1 a 10 12 14 16 *-
5'1
Clear ll
40%| __ _
Acceleration ”lhh- om mis’
_ s:l
- I.
d —--4----F—--4----+---H—---+--——F---4----F---4
Ida “lo ‘I 2 4 0 8 10 12 14 10
-§l
Clear Il:
4091.. __ __ _ -__L_-.____L-_-______,
VICIOI"
I: call } ! macs I} Stop L«a«m¢_ll Bound Um..." imam M300“
1 VJafvan/Vhdow

 

 

m

Fmoviifgfiian’sfimation (pHET 2010)

AS the man moves, the graphs are made in real time. On the assignment, students
replicated a series of situations, and then drew the resulting graphs. They reflected on the
various Situations they had drawn, tO see if they could come up with an explanation of
when acceleration is not equal to zero. Finally, they were given a distance graph, and
asked to use it to make a velocity graph and an acceleration graph, using the simulation to
check their work and understanding. This final question was very much like what they
would do in the coming days in their lab, on worksheets, and then finally on their

assessment.

16

Following the simulation, was the graphing motion lecture (Appendix C2). The
lecture consisted Of examples of different motions and how they would be graphed, as
well as how values can be determined from the slope and area under the graphs. This
was followed by the Graphing Motion Demonstration (Appendix C3). Students were
asked to match their movement to the motion on the graphs. Initially students attempted
this on their own. However, eventually each example was discussed thoroughly with
them, and the class analyzed exactly what should be done to match the graph. In this
way, the demonstration resembled a guided inquiry lab because students were given a
problem (a graph to match) and were asked to figure it out with help from the instructor.
Students were then given the Graphing Motion Worksheet (Appendix C4) to complete.
One example was done with the class step by step, and then they completed the rest on

their own.

In the next few days, students were given several other problem sets dealing with
graphing motion and numerically solved straight line motion problems. Half of a class
period was spent completing the Graphing Motion Lab (Appendix C5) which was
specifically written to fit into one class period. Students completed the lab in groups of
three or four. They turned these labs in as a group, and students were informed that

everyone in the lab group was responsible for personally knowing the material.

Following these assignments, free fall problems were addressed specifically,
integrating graphing into the assignments. Students completed the F rec-fall Lab, and

constructed graphs to fit the data. These assignments also dealt with graphing motion

17

and helped to solidify student reasoning. The Graphing Motion Post Test (Appendix B2)

closed the unit.

Unit Two: Projectile Motion

Students completed the Projectile Motion Pre-test (Appendix B3) directly after
the Graphing Motion Post Test. The main objectives on the pre-test were to determine if
students understood both how a projectile travels, and what changes occur in horizontal
and vertical motion as the projectile moves. Students were also asked some conceptual
questions to see if they knew that a horizontal velocity does not have any effect on
vertical velocity. Afterward, a discussion on projectile motion took place (Appendix C7).
The independence of the x and y components as well as how time links them was
discussed. Finally, some quantitative problems were done on the board to serve as
examples. On this initial lecture day only horizontally launched projectiles were
discussed. Also, some of the Projectile Motion Demonstrations (Appendix C8) were

performed.

For homework that night, the Projectile Motion Simulation was assigned

(Appendix C6), once again through PhET (Figure 2).

18

 

 

f?
userchoice ‘
mason) heighxm) timem tankshell

golflmll
mglddegrees)Z]
. .. . r I, \:l
Mani
dimelefim)E

,,. Air Resistance

0

 

 
   
 
 

 

 
 

Q
MIT

71 Sounc'

   

 

 

   

. ‘ 7 ‘
10.56m

 

ammummmm V a: (in -

Figure 2: Projectile Motion Simulation (pHET 2010)

The projectile simulation gave a choice of several different items to fire, allowed the user
to change the angle of the cannon, to change the mass, size, and speed Of the object, as
well as to turn air resistance on or off. Students turned air resistance Off and on, and
played with the simulation, using several different objects, so that they observed that it is
only air resistance that keeps objects of different Sizes from following the same path.
They manipulated a series of variables and listed whether they hit the target or not, and
made observations as to time in the air, trajectory, horizontal and vertical distances
traveled. The simulation included a tape measure which can be manipulated to measure

distances on the screen.

The following day a discussion was held which included velocity vector analysis
and projectiles fired at angles. The Projectile Motion Lab (Appendix C10) had two parts.

Part A involved firing a projectile horizontally, and then calculating the muzzle velocity.

19

Students used this information for part B, in which they fired at a series of angles,
measured the range of the projectile, and compared it to the predicted range using
velocity from part A. This lab echoed some problems students had done on the Projectile
Problems Worksheet (Appendix C9) the day before, but with numbers they measured so
that they could connect the two concepts. Because the power repeatedly went out during
school hours this week, the projectile unit had to be shortened and the remaining
Projectile Demonstrations (C8) were postponed until after the Projectile Motion Post Test

(B4) was given.

Unit Three: Conservation of Momentum

The Conservation of Momentum Pre-test (Appendix B5) primarily addressed
collisions and the changes in velocity between Objects of the same mass and of different
masses. Students were asked to explain why increasing the time of contact between
objects will decrease the force between them as long as the change in momentum remains

the same, referring to the impulse-momentum theory.

The unit began with a lecture on momentum, explaining the differences between
inertia and momentum, how to calculate momentum, and then the impulse-momentum

theory (F t=mAv). Momentum Demonstrations were also included (Appendix C13).

The Conservation Of Momentum Simulation (Appendix C11) was assigned for
homework. It was shortened due to time constraints, so that the students chose just one

elastic collision and one inelastic collision to analyze quantitatively. Students

20

manipulated the masses and velocities of the Obj ects and listed the final velocity of each
mass, after the collision. The students were asked to calculate initial and final
momentum as well as kinetic energy. The simulation allowed the user to change between

elastic and inelastic collisions (Figure 3).

"nut-fl-Q_ fl...--'o<--——— -——-4_-. ._. .. ‘1‘ -.. __._ .

 

 

3 www.mw-NKMO/My‘whua "T ' D " ' OI- ' "'9" “‘7' I°°"" 0' 5’ I3 Ci I 3:»
Cat mass anal velour}- mnent velocity
am Can [To— "—lToTo" lion 0 "-
am Can fio [0.0 |o.o
“a - 1.0 Scenarios 5' Sides elastically reflect

“g lmI-mz «use .| Pyommums

 

_LLLQIJMIJ

“KAI-Track

mmehmhm Touamsohdmoflhmhlhdmbnmadfl'fi'. M"Slo"atuythoupauolhm
Mh'fi'flmiufiapfl. TommyurmMMOMQfi-h—fiomm-ul,aflmMflwufiaflan-yuhoflfioam'
MI. You-ayakood'llle't'mihlvobciiund-um'-fieamhtobfllflfiomhgfiocmbnyMolfioMflafl"#3". "abho'WIa-amol
hehficiyolam hnwvfioolmb‘um-ohsdccofibqivflnkhofitmibu Munmwuflimumu-fi’ohafic. A.“
vfidmhaMMthfimmMMMwwfi Cougbbholmmflmmmm Mutant.
whdacfiuhmflbwmwhu

 

Ben. I T I T " efimimxw’fim

- Figure 3: Conservation of Momentum Simulation (Michigan State University, 2010)

T4" moms .

Students were introduced to conservation Of momentum through the Conservation
of Momentum Demonstrations (Appendix C13). They also learned which values change,
and reviewed example problems in both elastic and inelastic collisions (Appendix C12).
A frictionless track and collision carts were used to demonstrate the various situations.
Masses and speeds Of the carts were changed while students were asked to make
predictions as to what would happen. Students also examined and experimented with a
giant Newton’s Cradle. Students worked on some problem sets dealing with
conservation Of momentum calculations. Finally they performed the Conservation of

Momentum Lab (Appendix C14) using the collision carts. The lab was done as a class

21

demonstration due to equipment shortages, time constraints, and difficulty in collecting
the data with available equipment. Students were asked to do all the data set calculations
for an elastic collision, inelastic collision, and with an unknown mass added to the cart on
their own or with a partner’s help. Following this demonstration, students completed
book problems on conservation of momentum before the Conservation of Momentum

Post Test (Appendix B6), which was given three days later.

Student Surveys

Students were surveyed as to their opinions on the various types of activities that
were used. Surveys (Appendix B) were given up to two weeks after the unit had been
taught and respective post tests were given. When students took the survey, they knew
what their post-test scores were. The surveys asked students to rate each teaching type
that was used (simulation, lab, problem set, discussion, demonstration) on a 1-5 basis, 1
indicating that the assignment did nothing to further their understanding of the topic and
5 indicating that the assignment was pivotal to their understanding. They were also asked

to make comments about each assignment type.

Final Exam

The final part of this study looks at student retention of the concepts taught by

asking two questions per study topic. Questions that dealt with the three topics above on

22

the Final Exam (Appendix B7) were pinpointed. Time constraints for the final exam

caused there to be only two questions per topic assessed on the final exam.

23

Results/Discussion

The results and discussion sections have been combined due to the large amount
Of data specific to each Objective. In this way, the data were analyzed much more
effectively. On the pre- and post-tests, questions were identical unless otherwise noted.
Paired pre- and post-test questions (Appendix F) are listed in this section in terms of the
number on the pre-test, followed by the number on the post-test (ex. #1/3: Pre-test #/Post-
test #). Questions marked with a “P” indicate that it is a Short answer or quantitative
problem, and questions marked with an “MC” indicate that it is a multiple choice or
true/false question. Pre-tests were comprised of 10 questions, whereas post-tests always
had more questions, which is the reason why paired questions do not have matching
numbers. Results were analyzed using a paired Student’s T-test (n=25 unless otherwise
noted) for each set of itemized pre/post-test questions. Other data in this section come
from anecdotal comments by the researcher. For pre/post-test scoring rubrics, see

Appendix D; for Objectives, see Appendix A.

Unit One: Graphing Motion

Students indicated after taking the Graphing Motion Pre-test (Appendix Bl) that
they remembered seeing and drawing these motion graphs in the introductory freshmen
science course, but that they didn’t recall any specifics of how to draw them. During the
Graphing Motion Lab (Appendix C5) in which they used graphing software,
conversations overheard by the researcher were encouraging. Students actively worked

together to closely match the graph to their movement, explained to each other why the

24

line had a negative slope when it did, or talked about why there might have been a spike
in the graph. On the other hand, there was a lot of confusion with the Moving Man
Simulation (C1) that they had done as a homework assignment. Many students failed to
use the program effectively and were frustrated. The Graphing Motion Post-test
(Appendix 82) scores overall showed a better understanding Of graphing motion than has
been Observed in years past, based on the graphs students constructed for questions 4P
andSP. Results from the paired Student’s T- test for unit one Show that the probability of

the results, assuming the null hypothesis, is 0.004.

Objective A: Create graphs using position and time.

Objective A was taught in several ways. Students used graphing software to view
how their movements looked on a graph in real time, used a computer simulation to see
how different movements looked when graphed, and completed related homework
questions. Three pre/post assessment questions dealt specifically with Objective A.

Results from these questions are shown in Figure 4.

25

 

Objective A

 

 

   

‘8’ _
f:
o
O
&
53
O)
8
0
9..
I"/5" 33/313? Average
Question Number

I Pre-test I Post-test

 

 

 

Figure 4: Graph Of Objective A Pre/Post-test Results

All three paired questions were not the same between pre- and post-test. The
reason for this is that post-test graphs contained additional segments, making them more
difficult. These data Show that while students had slightly lower scores when solving the
velocity-time graph (#7/5P) as compared to the distance-time graphs (#6/4P, #8/3bP),
indicating this is the more difficult problem, both Of these problem types had nearly the
same difference between pre and post-test. Question #6 had a difference of 52% while #7
had a difference of 40%. Question #8 asked students to read a description of motion and
translate this into a velocity-time graph. This was a concept that students did fairly well
on to begin with, 46% Of students getting the question correct on the pre-test. On average
for objective A, scores increased by 38% between the pre- and post-test. Question

numbers 4P and SP on the post-test required students to interpret a distance time and

26

velocity time graph, respectively. Students seemed to have an easier time when
beginning with a distance vs. time graph. Additionally, the questions on the post-test
were extremely difficult, as compared to the pre-test. This is because the post-test graphs
that students analyzed contained many different segments of line that had to be drawn
correctly on the corresponding graphs. According to the rubric (Appendix D), to get the
full point on the question they needed to get every single part correct, whereas to get 0.5
they needed to get more than half of the question correct. On question number 4P, the
mode was 1 while the mode on number 5P was only 0.5. Anecdotally, I felt students did

much better on these three questions than they have in years past.
Objectives B and C: Describe and analyze position-time and velocity-time graphs.

Objectives B and C were very similar which is why they were analyzed together.
As shown in Figures 5 and 6, three pre/post assessment questions dealt specifically with

objective B and two pre/post assessment questions dealt with Objective C.

27

 

Objective B

 

 

 

 

,_, __ _ _ _ - H
8
I:
c
U
80
g
d.)
8
0
On
03/ 12mc tlS/ 15mc #9/8p Average
Question Number

I Pre-test I Post-test

 

 

Figure gin-Graph of Objective Bil’relPOStl-te—sfl—{e—SUIIS _ I _

Data Show that overall student understanding improved greatly between pre- and
post-tests. On average there was a 45% increase between the pre- and post-test score.
The largest gain between pre- and post-test was on pre-test question #3 and post-test
question #12 multiple choice. 28% of the students in the study did not get post-test
question #12 me correct. Of this 28%, not one student chose letter C, which had a
negative slope. This indicates that students clearly understood the relationship between
slope orientation and positive or negative acceleration. However, they did not all make
the connection that acceleration translates to a line that is curved upward. Almost every
student who got this question incorrect chose letter A, which shows a linear slope,
indicating constant speed instead of increasing speed. Questions #5 and #9 had similar

differences between pre- and post-test scores. Interestingly, #9 appeared to be a very
28

 

simple question and a much higher score was anticipated. The part that caused the most
trouble for students was the downward sloped section of the graph. Many students stated
that the ball stood still, was “dropped”, and then stood still again. I believe that if the
object being graphed had been a person’s movement, many more students would have ‘
gotten this correct. However, it Should not matter what the object is, students should be

able to interpret the graph.

 

   

ObjectiveC

100
O
“:3
o 60 ~
0
no") 40 -
2 20
O
O
8 0
9..

#4/13mc 10/ 14mc Average

Question Number

 

 

' Pre-test ' Post-test
Figure 6: Graph of Objective C Pre/Post-test Results 7

The most puzzling result related to objective C was the decrease in score
between pre- and post-test scores for question #4/13mc. Only 52% got this question
correct on the post-test, and on the pre-test 80% got the question correct. The majority of
the 48% who got this incorrect chose letter D, which would have been the correct answer,
had this been a position time graph. I believe this demonstrates one of the greatest
problems students face when dealing with graphing motion. Students have difficulty

When switching between position, velocity, and acceleration graphs. Of the 80% who got

29

this question correct on the pre-test, most stated in their explanation that “it is the only
negative graph” or “because it is going in the Opposite direction as the positive
acceleration”. It seems that after learning about graphing motion they over-analyzed the
graph. Question #10/ 14 asked students to “choose all answers that apply.” On the post-
test question, 36% Of students chose only one of the correct answers, and 40% of
students chose both correct answers. In assigning point values as explained in Appendix
D, this averaged to a score of 62%. On the pre-test question, only 8% of students got
both correct, while 60% of students got one correct; according to the point values
assigned, this averaged to 42% correct. The common misconception this problem deals
with is that the word acceleration only means increasing speed, when in reality it also
means decreasing speed as well as a direction change. Consequently, many students

chose letter “e” only, on the both the pre- and post-test.

Objective D: Use area under the graph and slope to determine values from a velocity time

graph.

Two questions dealt with objective D. This objective was taught and

assessed primarily through lecture notes and problem sets.

30

 

Objective D

 

 

 

 

 

 

 

4.;
8
t:
o
O
i:
5
8
d)
a,
#1/9mc #2/10mc Average
Question Number

 

I Pre-test I Post-test
Harm{'aagrsr‘osjieawe D manages} REQfiItSWWW' W

There was an average gain of 22%. Predictably, question #1/9mc had a
slightly greater gain. I attribute this to the fact that most physics students have extensive
knowledge of slope, Algebra 2 being a prerequisite for physics. However, finding the
area under a line graph is much less familiar to students. It is not until a calculus class
that students are exposed to this idea in any depth. Looking back at all of the graphing
motion objectives, it is interesting to note that this objective was the one with the lowest
average post-test score. One explanation could be that this was the only objective that
was assessed solely through multiple choice. This could be the reason why there was a
lower overall score since students could either receive 1 point for a correct answer or 0

points for an incorrect answer. It was also taught solely by lecture and problem sets.

31

 

Unit Two: Projectile Motion

On the Projectile Motion Pre-test (Appendix B3), generally it was found that
students were not knowledgeable about the mechanics of projectile motion. On the
Projectile Motion Post-test (Appendix B4), students did pretty well and there were some
very good answers on problem # 8, the sailboat and rock question. However, basic
mathematics were a problem in that students showed an inability to separately deal with
the x and y components. Results from the paired Student’s T-test Show that the

probability Of the data occurring, assuming the null hypothesis, is 0.001 (n=22).

Objective E: Identify changes in speed and direction for everyday examples of

projectiles.

For objective E, questions were asked about how vertical and horizontal
speed change along a projectile’s trajectory as well as the path of projectile motion.

These Objectives were taught through many demonstrations and examples during lecture.

32

 

Objective E

rill

#2/2 #3/7a #4/3 #S/6c 86/4 #7/Sa Average

 

Percentage Correct

 

Question Number

I Pre-test I Post-test

 

Figure 8: Graph of Objective E Pre/Post-test Results
The data show that on average there was a 40% gain between pre- and
post-test score for this objective. Question #2/2 had the highest pre-test score, and
students only gained 14% between assessments. This question simply asked what the
path of a projectile is which most students knew when the unit began. Of the 19% who
got this question incorrect on the pre-test, 12% of these students answered that projectiles
do not follow a predictable path. The other 7% either guessed (as they stated in the
explanation) or did not answer the question at all. On the post-test, 95% got the questions
correct. The largest gain in score was 61% on question #7/5a. This question was
different between pre- and post-test, but both asked students to draw or choose the correct
path of a projectile that was being dropped from a moving object (plane or flying bird).
On the pre-test, most students recognized that the object would not follow a straight line
Path (answers b or c) and instead chose a or d. However, only 30% of the class chose the

correct answer. 40% of students chose letter a, the path curved backward and down.
33

 

This shows that students did not take into account that the projectile should move in the
direction it was already going instead of backward, as if from the perspective of the bird
or plane. On the post-test, students were asked to draw the path themselves. All drew it
directed forward this time, but if a student lost points, it was because he/she drew a
straight line path as Opposed to a curved path. There was a very low post-test score on
#5/6c, which also differed between pre- and post-test. The pre-test score of 41% was
expected, but the post-test score was not. The post-test question asked students to
describe the vertical velocity Of a ball that is dropped. 28% Of students answering this
question described the ball as being thrown up and down, and therefore said velocity
would first decrease, then become zero, then increase as it moved downward again. This
caused these students’ scores to be 0.5/1, decreasing the overall average. Other students
seemed to get this question confused with the horizontal velocity vector, and instead
described that. Question #3/7a also differed between pre- and post-test: on the pre-test,
students only needed to draw arrows the proper Size and direction, whereas on the post-
test students drew this as well as quantitatively solved for their values. This is the reason
that scores did not increase on this paired question as much as on other question; students
were asked to get more items correct in order to receive full credit. Overall, the data
show that students understand how projectiles travel. The breakdown in their thinking
seems to be both in translating their thoughts into drawings or diagrams and also keeping

vertical and horizontal velocities straight.

M: Apply the independence Of horizontal and vertical velocities to solve

Projectile problems.

34

Many students struggled with objective F for the entire unit. This was
taught through the Projectile Motion Lab (Appendix C10), the Projectile Motion
Simulation (Appendix C6), and many class examples and homework assignments. Since
students could not be expected to have any idea how to solve numerical problems on the
pre-test, conceptual questions that were related to understanding how horizontal and

vertical velocities have no effect on each other were asked.

 

Objective F

100
90 ~
80
70 -
60 '
50 ‘
40 >
30
20
10 ~

 

Percentage Correct

#1/1 #9/8 Average

Question Number

I Pre-test I Post-test

 

Figure 9: Graph of Objective F Pre/Post-test Results

The data show a relatively small gain on this objective. #1/1 was a true/false question so
students either got 1 point or 0 points. They also had a 50/50 chance if they guessed.
There was only a 22% gain on this question. Question #9/8 was probably one of the

hardest questions that asked on any of the assessments. It asks students whether a rock

35

 

dropped from the mast Of a boat will hit the same place on a deck when the boat is
stationary vs. moving. 35% of students got this question correct on the pre-test, but most
of this came from partial credit. Only one student got full credit for this question. On the
post-test, 100% Of students received at least partial credit, and 28% of students got full
credit. Students who received partial credit did not sufficiently explain why the rock
would hit at the same place on the deck. Most failed to draw a picture that fully
explained or backed up their reasoning. The average pre- and post-test scores are 42%

and 68%, for a 26% increase.

Objective G: Understand that time iS common to vertical and horizontal components Of

motion.

Two questions dealt specifically with Objective G. Students were shown
a. demonstration in which one ball was given a horizontal velocity while another was
dropped straight down, both released at the same time. They were able to Observe that
there was no difference in “hang time” between the two balls. Additionally, students

were taught this concept mathematically, solving problems for practice.

36

 

 

Objective G

100
80
60
40
20

 

Percentage Correct

#8/6a #10/6b Average

Question Number

I pmtest u Post-test

 

 

FigUIe 10: Graph of Objective G Pre/PoSt-test Results

Questions #8 and 10 are very much related. On the post-test, the two
were part a and b of the same question. The pre- and post-test questions were different,
but both dealt with the fact that it will take a projectile the same amount of time to fall to
the ground, regardless of whether it has a horizontal velocity or not. The difference
between pre- and post-test was that on the pre-test questions, students were asked to
explain whether projectiles would hit the ground at the same time or not when one was
given a horizontal velocity. On the post-test quantitative questions asked students to
determine exactly how many seconds each object would be in the air if they were
dropped at the same time. Questions showed almost identical percentages correct on
both the pre- and post-tests. Overall, students had sufficient understanding of this
concept. On the pre-test most students said that the object that was moving both
horizontally and vertically would take longer to reach the ground than the one traveling
only vertically. A typical student response to number 10 was “the bullet that is being

dropped will hit the ground faster, because it doesn’t have as long of a way to go before it
37

hits the ground.” On the post-test, 33% of students who got 6a and/or 6b incorrect could
be attributed to mathematical errors. They had the correct equation and variables but
then solved the problem incorrectly. The others seem to be a failure to choose the correct

equation and to input the correct variables.

Unit Three: Conservation of Momentum

Results from the Conservation of Momentum Pre-test (Appendix BS)
Show that most students could equate conservation of momentum to everyday situations,
such as throwing an object forward and being pushed backwards, but when it came to
other examples, the results were mixed. Later in the unit, after looking over the
Conservation Of Momentum Simulation (Appendix C11), it was noticed that most
students did very well on the calculations of momentum and kinetic energy. The problem
was with the questions “Is momentum conserved?” and “Is kinetic energy conserved?”.
Although the majority of the students got the calculations correct, they answered these
questions incorrectly. It is the researcher’s belief that this is because they thought that
momentum, not in the total system, but just in the individual Object, should remain the
same. Based on Observations, students did very well with the Conservation of
Momentum Lab (Appendix C14). They seemed to really understand what was going on,
and the most difficult part, the unknown mass determination, went over well.
Conceptually, I thought that the students did well. The biggest problems were the same
ones they were warned about over and over again: unit conversions (g to kg, km/hr to

m/s), paying attention to directions by making Opposite directions Opposite signs, and

38

using Ap as pfinal-pinitia] and not vice versa. Overall, the students who failed to fully

understand the mathematics of conservation of momentum still seemed to have a very
good grasp of the concept. It was encouraging to see that students who got many of the
calculations incorrect still had very good, thorough answers for the explanation problems.
Results from the Student’s T-test Show that the probability of this occurring, assuming

the null hypothesis, is 0.000 (n=20).

Objectives H and I: Explain and calculate how time Of impact and force Of impact

influence each other.

There was only one question on the assessments that examined Objectives
H and I together, which are very similar. The pre-test question asked about the concept
of follow through in baseball, and why it is effective. The post-test question asked about
why an egg will not break when it hits a towel as Opposed to a wall. Both questions have

to do with the impulse momentum theory.

39

 

Objective H and I
100

80
60
40

20

Percentage Correct

 

10/13c
Question Number

 

' Pre-test I Post-test
Figure 11: Graph of Objective H and I Pre/Post-test Results

 

 

On both the pre- and post-test, partial credit was assigned, as referenced
in Appendix D. The scores were 40% on the pre-test and 60% post-test, with a
difference of 20%. On the pre-test, several students had some idea as to why follow
through was important, but couldn’t explain it satisfactorily. A common answer among
students was “you give the ball more energy to travel farther”. While this shows that the
student understands the concept at a basic level, it does not demonstrate that they
understand the relationship between time of contact and change in momentum. Only
16% of students had a sufficiently correct answer to warrant full credit. The most
common score on the pre-test question was 0/1. On the post-test, the most common score
Was 1/ 1 points, with 44% of students earning full credit and 32% earning half credit. The
most common reason for loss of points on the post-test was students simply saying “the

towel cushions the egg” which, while true, is not a “physics” explanation.

40

Objective J: Apply conservation of momentum to solve simple collision problems.

Objective J deals with the student being able to apply what they have
learned about conservation of momentum to solve simple mathematical problems. Five
questions assessed the students’ knowledge on this topic. On the pre-test, students were
asked to choose what would happen after a collision of two objects in varying situations,
such as deciding whether the object would be moving faster or Slower. Typically,
physics students come into class with a fair amount of knowledge of this from the world
around them. However, they do not always make the most accurate Observations, so the
data sometime surprise them. On the post-test, students were asked to solve problems
numerically. This involved choosing the correct Sign conventions, and matching the
correct mass with each velocity. This Objective was taught in many different ways.
There were many demonstrations, a class lab on conservation of momentum where they
calculated momentum Of Objects before and after collisions, as well as numerous

individual assignments for which they had to calculate momentum.

41

 

Objective I

so 4 .

so . W

40 -

20 i

o , .

#1/ 10 #3/ 3 #4/8 #S/ 6 #8/143 Average

   

Percentage Correct

Question Number

I Pre-test I I Post-test
Figure 12: Graph of Objective J Pre/Post-test Results

 

 

 

Figure 12 shows that the greatest gain in score came on question #4/8,
and the smallest gain was on question #8/ 14. Questions #4/ 8 and #5/6 differed between
pre- and post because the post-test had students solve the problem quantitatively.
Question #4/8 was on the change in momentum of a bowling pin and ball system. The
pre-test simply asked about relative speed (faster, Slower, the same) while the post-test
asked students to come up with a numerical answer. Question #5/6 and #3/3 were similar
in percentage differences, pre to post. The question with the lowest difference between
pre and post was #8/14a. The question asked students to draw a diagram showing two
snowballs of unequal masses but equal speeds colliding head on. Most students seemed
to inherently understand this situation through experience with everyday interactions
between objects. 44% of students on the pre—test drew a before and after picture, but the

after picture showed a large snowball without any velocity vector. Whether students

believed the snowball would come to rest, or just neglected this fact is not clear. On the
42

post-test, 36% of students still made this same mistake. Another part of this same
problem asked students to figure out the final speed of the combined snowballs after the
collision. 56% of students who got the diagram wrong still got the numerical part of this
correct. This seemed to be more of a problem with their diagramming skills than their
understanding of the problem, or else more likelier, a problem of using an algorithm

without having conceptual understanding.
Objective K: Predict how large and small masses will be affected in a collision.

Objective K was taught using the Conservation of Momentum Simulation
(Appendix C11), discussion in class, Conservation of Momentum Demonstrations
(Appendix C13), the Conservation of Momentum Lab (C14), as well as several problem

SCIS.

 

Objective K

100 -
90 ‘
80 -
70 '
60 ~
50 .
40 ~
30 ~
20 ‘
10 ‘

 

Percentage Correct

   

82/2 #6/5 #7/9 Average
Question Number

 

I Pre-test I Posttest

 

Figure 13: Graph of Objective K Pre/Post-test Results

43

‘7‘

ill

in

The data related to this objective Show a wide range of results among
questions. Question #6/5 (Figure 13) was the only set where the pre- and post-test
questions were not identical. The pre-test question asked students to predict what will
happen when an object is thrown forward whereas the post-test question asks the question
quantitatively. This question showed an 18% change between pre and post. The post-test
score was reasonably high compared to other post-test question results in this unit. This
can be attributed to the fact that many demonstrations and examples of this Situation were
done. Question #7/9 showed the greatest percentage improvement, from 35% to 64%.
This demonstrates that a majority of students learned the difference between elastic and
inelastic collisions, and also understood that if one object loses momentum in a collision,
the other has to gain it. The smallest gain between pre- and post-test was for #2/2, which
indicates that instruction did not have any real effect on student understanding of the
concept Of small and large masses in collisions. Although this question seemingly
assessed the same Objective as the other two questions discussed, students did not do
well. Perhaps the wording of the question caused it to be confusing Since it does not pose
a Specific situation for students to analyze; it instead refers to “two Objects with different
masses.” If the question instead named Specific Objects such as a car and a semi truck,

Students might have done better.
Objective L: Analyze why seat belts might be more important in autos than in buses.

There was only one question that covered Objective L, because this is a

Very specific state objective dealing with seatbelt use in buses vs. cars. This Objective

44

was covered through explanation with many class demonstrations, as well as by

calculating conservation of momentum problems.

 

Objective L

100 . L
90 L
70 l
so

40
30 :~ .
20
10

Percentage Correct

 

89/15

Question Number

 

I Pre-test I Post-test

Figirre 14: Graph of Objective LPre/POst-test Results

Figure 14 shows that on the post-test, 92% of students got this question
correct. Most students on the pre-test made the connection that bigger size means less
effect on the people in the vehicle when hitting a smaller vehicle, but could not give a
sufficient explanation as to why this happens. Some simply said, “because the car is
smaller”. On the post-test, students as a whole had much more complete answers and
referenced conservation of momentum in their answers. One example is “because you

gain more momentum in a car during a crash than you do in a bus”.

45

 

Student Survey Results

The students were given a survey for each unit (Appendix E) to assess how they
felt the various teaching methods and tools helped them. A five meant that they really
thought the assignment helped them to learn and a one meant that they though the

assignment did nothing to further their understanding. They were also asked to provide

 

 

comments.
Average Student Survey Results
on 2'3
{-5 325
N 3.0 -
5
C , -
w 1.5
E 1.0
U) 0.5
0.0
m .1. 3
a a 8
a a g
E E g a 3
m 3 .9 tr. 2 3

 

F igIIrWe 15: Graph of Student Survey Results
Overall rankings were very close to each other (Figure 15). Students ranked notes
the highest at 4.0/5.0 and simulations the lowest at 3.0/5.0. It is interesting to note that
they ranked the traditional school activites (notes, problem sets) the highest, and gave the
lowest ranking to simulations. Most students commented that the simulations were very
confusing. They had trouble following the directions and manipulating the objects. A
few students said it helped them to visualize the real world situations but it seems like

most were detracted by the confusion that it caused. In class, several students indicated

46

that they did not like the lack Of step-by-step instructions that they normally are given. In
hindsight, it seems as though more guidance could have been given to the simulations.
There were directions on how to use each simulation, but many times students do not

read directions at all. Perhaps if the simulation was used as a class activity, it would be
more effective. Students said that the notes and problem sets help them study the most of
anything else done in class. I think they also like the familiarity of these two
components. Although they complain about them quite Often, it seems this is the way
they believe they learn best, and are uncomfortable with other teaching activities. The
highest average score that students gave was for the Conservation Of Momentum
Demonstrations (Appendix C13), with a score of 4.3/5.0 (Figure 15). Students said it

helped them to visualize the problems and to learn from real-life scenarios.

Retention of Knowledge Over Time

Retention of knowledge over time was analyzed, by looking at final exam scores

and comparing them to the students’ overall post-test scores.

47

 

Final Exam Scores vs. Post Test Scores

 

100
g 80
g 60
a, 40
is."
a 20
8
g o
‘14

Graphing Motion Projectile Motion Momentum

I Post-test score II Final Exam Score

 

 

Figure 16: Graph of Final Exam vs. Post-Test Scores

One would expect students to forget what they learned as time goes by, and it is
one of our goals as teachers to try to minimize that. As the data in Figure 16 show, this is
the trend for projectile motion and momentum, but there is a surprising trend for graphing
motion. In graphing motion, the scores actually went up between the post-test and final
exam. One explanation for this is that students learned from mistakes they made on tests
since they are encouraged to review all old quizzes and tests before the final exam. A
more likely explanation is that these two questions were easier than some of the questions
on the post-test. Projectile motion and momentum both lost around 20 percentage points
in the 4-8 weeks between when the material was taught and when the final exam was
administered. This trend seems fairly normal (but discouraging) based on my past
experience with final exam scores. One other factor to consider is that the topics are
listed here in the order they were placed on the final exam. Many students were
eXtremely rushed by the time they reached the end of the exam and, therefore, did not

48

believe they had the time to really attempt the momentum questions, or even the

projectile motion questions.

49

Conclusion

Overall, the units that I taught for this study were fairly effective. Subjectively, I
noticed many improvements in student understanding that came through the changes that
were enacted. Simulations seemed to be the biggest down side to the changes made,

although I do still plan to use them with some modifications.

Unit One: Graphing Motion

I heard some great conversations going on between students in the graphing
motion section, especially in the Graphing Motion Demonstration (Appendix C3) and the
Graphing Motion Lab (Appendix C5). I made the demonstration into a sort of
competition as to who could get the best graph match and they were all eager to try as
well as to help out the person who was trying it. The lab activity was also quite
effectively carried out in the time that was allotted for it (30-40 minutes). I will continue
to do this lab based on favorable student reaction (Figure 15), as well as the data
supporting that it was effective (Figures 4-7). Another effective assignment was the
GraPhing Motion Worksheet (Appendix C4). Students needed to put together everything
We had done up to that day and really think, “Does this make sense; do these graphs agree
With each other?” I saw a marked improvement in student understanding of how to graph
motion between this year and previous years. In previous years on the post-test, about
50% of my students would get these questions completely wrong, but this year scores

Were much improved, with at least half getting questions 4P and SP 100% correct (Figure

50

4). Students used the worksheet as a study guide and several students came in before the -
test to review the worksheet and similar questions with me. On the post test, not one
student got the two problems completely wrong; previously they got either the distance-

time graphs or the velocity-time graphs incorrect.

The Moving Man Simulation (Appendix C1) that I assigned was by far the
biggest disappointment in this unit. As research suggests, simulations should only be
done if there is a lack of equipment available due to expense or limited resources, a
history of inaccurate or contradictory results, or data collecting software/hardware
reliability. (Brant, Hooper, & Sugrue 1991) A Simulation was assigned to students
because graphs made by the software tend to be “messy” since the motion detector picks
up any motion at all. The simulation was used to give students nice smooth graphs to
work with before they were exposed to real-life “messy,” graphs. However, students
were so confused by how to use the simulation that they could not get past this to learn
anything. If I had provided 10 minutes at the end of class for students to log on and try
out the simulation with me, then I believe it would have been much more effective.
Instinctively, when given an assignment, students want to Skip directions to save time,
which usually hurts them in the end, as it did in this case. Also students are not used to
this kind Of assignment. They were not given cookbook-type directions, but instead were
asked to experiment and play around with the simulation, trying to replicate graphs. As
the literature shows, these types of instructions tend to frustrate students more, especially
the lower level students (Royuk & Brooks 2003). I find that many times when students
are asked to do something like this, especially the mid-lower level students, they will give

up if they don’t understand instructions within a few minutes.
51

Overall, the notes and problem sets were what the students felt the most
comfortable learning through, Since they are so familiar to them. Students ranked the
notes and problem sets highest, both with 4.0/5.0 on the rating scale (Figure 15). Except
for one student who said “Content difficult to master”, everyone else said they really
liked the problems because they “help me see different scenarios and how problems
might be written on tests and quizzes.” It is troubling to see that students are so focused
on the grades assigned, and less that they actually master and understand the material.
However, the Seaholm High School community is especially focused on grades as many
students go on to prestigious colleges and universities. Perhaps if tests and quizzes were
tailored a little more to ask about the discussions held, labs taught, and demonstrations,

students would feel more invested in mastering the content.

Unit Two: Projectile Motion

In the projectile motion section, results were similar to those of graphing motion.
The Simulation once again had the lowest rating (3.2/5.0), and this time problem sets and
labs were tied for the highest rank (4.3/5.0) (Figure 15). For this unit, I was able to ask a
few more short answer questions related tO their understanding of projectile motion that I
had not asked in the past. These questions allowed me to see who understood the
concepts, who did not, and if they did not, I was able to pinpoint where their

understanding was insufficient.

52

For this unit, especially, students needed a lot Of practice; so much of the notes for
projectile motion consisted of problems and examples of how to solve them. Students
also completed several worksheets and problem sets which we then discussed in class.
Students indicated that this is how they learned best (Figure 15). According to
comments, students also particularly liked the demonstrations done. Unfortunately,
because of power outages and school events, the monkey demo had to be postponed until
after the post test, so I could not effectively assess its influence. For the observed
demonstrations, students needed to apply these concepts to new problems which not
everyone could do easily. This is where the class discussion during and after a
demonstration is very important. As the literature indicated, demonstrations are not very
effective at all if they follow a “Show-and-tell” method (e. g. Shepardson et al 1994). In

order to be effective they need to be more interactive, which I attempted to do.

The Projectile Motion Simulation (Appendix C6) proved to be quite confusing,
just as the Graphing Motion Simulation (Appendix C1) was. This Projectile Motion
Simulation definitely needs to be rewritten because after having one group of students
use it, I realize that there are some poorly worded questions. Also, when I use this next
year, I will either give some time in class to get started, or demonstrate on the TV
monitor how to use the program since, once again, it does not seem as though they read
the directions. In the future, I think I would also omit all questions dealing with air
resistance, because that is what students found the most confusing. If anything, air
resistance will be left to the end of the projectile unit, and ideal cases will be dealt with

first.

53

The Projectile Motion Lab (Appendix C10) went fairly well, except that once
again the power outage proved quite detrimental as it occurred during the lab in one of
my classes. We finished the lab in the dark but we were rushed and it was very hectic! I
did notice that students had an easier time figuring out how to solve the different parts of
the lab compared to previous years. I made a point of telling students before the lab that
they had learned how to solve the problems previously, and now they were going to use a
real projectile launcher to see if the calculations agree with the actual distance a projectile

moves. Most groups were very efficient and understood how to carry out the lab.

Unit Three: Conservation of Momentum

In this unit, the top level students could both accurately solve conservation of
momentum problems as well as explain them in writing. The middle and lower level
students had trouble with either mathematically solving the problems or explaining them
in writing, but rarely did they have trouble with both. This is very encouraging because it
indicates that even if students struggled to solve problems in one particular way, which

was expected for some students, they still understood the concepts.

The Conservation of Momentum Simulation (Appendix C1 1) got by far the worst
rating from the students (2.6/5.0) out of all three simulations (Figure 15). This was also
the most primitive simulation I used; there were not many free conservation of
momentum simulations to choose from. The Conservation of Momentum

Demonstrations (Appendix C13), however, were rated the highest, contrasting their mid-

54

range ranking in the other two units. Perhaps the simplicity Of the demonstrations is what

made them so effective, or what made students favor them so much.

The Conservation of Momentum Lab (Appendix C14) was done as a class, due to
lack of time with the end Of the trimester rapidly approaching. The students really liked
this format, and many commented on the survey that “most labs are confusing but this
one was helpful because we did it as a class”. The part we did as a class was the data
collection, which was quite difficult to obtain in this lab. After we got the data, students
compiled them and performed calculations to determine whether momentum was
conserved. I also had thrown in a twist: they had to find an unknown mass added to one
of the carts using conservation of momentum. I will definitely do this lab again, and I

will probably do it in the same way, as it was effective.

If students really understand what should happen in a collision, then they can
double check their mathematical answers to see if they make sense. This didn’t always
happen on the test, but I know some students did this based on interactions with them.
One aspect of student performance that was disappointing was that, despite my c_on_sm
reminders that Opposite directions indicate Opposite velocity signs, students still made
this mistake frequently on the post-test, resulting in scores to be lower than expected
(Figures 12 and 13). In this case, I am not really sure how much more I could have done
to change this. It seems to be a powerful force of habit. Perhaps using positive and

negative velocity more often in earlier units could remedy this.

55

Overall

I plan to use almost all Of the assignments and activities described here again.
The simulations helped student understanding based on data described previously, my
observations, and the literature, despite what students felt. However, on these
assignments I will definitely have to make some changes based on my Observations as
well as comments from students. The labs I did were all very effective. For the most part
students did very well on them and also rated them on average 3/5 points (Figure 15). In
the past I had a few labs due to time constraints because Of the additional material we are
asked to teach as well as trimester adaptations, I am extremely pleased to be able to fit
them in once again now that I’ve pared them down to the most important of concepts.
Since in a traditional laboratory setting students can use 40—60% of the time taking
measurements (Hucke & Fischer 2002), using probeware greatly decreases this time
commitment and allows one to complete the lab in a shorter amount Of time, or spend
more time discussing results. The Graphing Motion Worksheet (Appendix C4) was
helpful and will definitely be used again. Discussions and problem sets seem to be what
students feel most comfortable with (Figure 15) so I will continue to teach with these.
However, I believe that they do need to be supplemented with the labs and

demonstrations in every unit, as I tried to do for these units.

In the future, with budget issues on everyone’s mind, we are going to need to find
cheaper alternatives to labs, which is where simulations have a role. There have already
been some suggestions from higher up in our district that we cut out labs and instead

substitute simulations, which I completely oppose. Simulations are great to Show a

56

concept cheaply and quickly, and eliminate messy data collection. However, as shown in
my survey (Figure 15), students do not like them much or adapt to them very easily.
Also, there are SO many skills to be gained by actually experimenting instead of
manipulating Objects on a computer as the literature confirms. Unfortrmately, it may
become necessary in the future to switch to more simulations, in which case my research

and experience will prove useful.

The demonstrations will also continue to be used and I will continue to develop
my demonstration skills, and seek out new demonstrations to share with students.
However, as this research showed, demonstrations need to be changed from their
previously common “Show and tell” form. This means that I need to make a concerted
effort to engage students in discussion during and after, as well as connect the
demonstrations to other everyday world events. If this is done effectively, students will
be able to take what they learned in a demonstration and apply it to new events, as well as

explain them effectively.

The labs that I did were a blend of inquiry and cookbook type labs. In this way,
students felt like they had guidance, but they also had to solve a problem without being
told the answer or exactly how to get it. I think that I accomplished this effectively, and
the results Obtained through student comment and the surveys were positive (Appendix
G3). While students will always find labs challenging because they are asked to think
outside the box, labs are a very valuable and necessary learning tool. I will continue to
use them and will also examine the other labs I use to see if they can be altered to be

more like the style of the labs I used in this study.

57

I am pleased with the results of this study. The data Show that average student
understanding was increased by at least 30 points in each unit (Figures 4-14). This
demonstrates that the teaching methods used are effective. While students sometimes
prefer learning in some ways better than others, the data Show that students did
understand the Objectives that I had for their learning. I think that student understanding
of concepts was increased as shown by the data (Figures 4-14), and also, subjectively, I
saw great increases in student understanding of concepts as evidenced by questions they

asked and the discussions I had with them.

58

Appendix A

Objectives and Expectations Covered in Units

Graphing Motion
State Expectations

A. P2.1C Create line graphs using measured values Of position and elapsed time.

B. P2.1D Describe and analyze the motion that a position-time graph represents,
given the graph.

C. P2.2C Describe and analyze the motion that a velocity-time graph represents,
given the graph.

D. P2.2e Use the area under a velocity-time graph to calculate the distance traveled
and the slope to calculate the acceleration.

Projectile Motion

State Expectations

E. P2.1h Identify the changes in speed and direction in everyday examples of
circular (rotation and revolution), periodic, and projectile motions.

F. P2.2g Apply the independence of the vertical and horizontal initial velocities to
solve projectile motion problems.

Other

G. Understand that time is common to both the vertical and horizontal components.

Conservation of Momentum
State Expectations

H. P3.4f Calculate the changes in velocity of a thrown or hit Object during and after
the time it is acted on by the force.

I. P3.4g Explain how the time of impact can affect the net force (e.g., air bags in
cars, catching a ball).

J. P3.5a Apply conservation of momentum to solve simple collision problems.

59

K. P3.3b Predict how the change in velocity of a small mass compares to the change
in velocity Of a large mass when the objects interact (e.g., collide).

L. P3.3d Analyze why seat belts may be more important in autos than in buses.

60

Appendix Bl

Graphing Motion Pretest

 

>1
o

F"
o

 

.V‘
o

 

 

P
0

9°
0

 

Velocity (m/s)

.N
o

 

p—s
O

 

 

 

 

 

 

 

 

0 2.0 4.0 6.0 8.0 10.0
Elapsed time (s)

1. What is the average acceleration of the graph shown above?
a. 0.5 m/s2

b. 1.0 m/s2

c. 2.0 nr/s2

d. 0.0 m/s2

Explain why you chose the answer you did:

 

 

 

 

61

2. What is the displacement for the first 4 seconds of the graph above?
a. 16 m
b. 8 m
c. 4 m
d. 12 m
Explain why you chose the answer you did:

 

 

 

 

3. Which distance vs. time graph shows constant positive acceleration?

 

 

 

Explain why you chose the answer you did:

 

 

 

 

62

4. Which velocity vs. time graph shows constant negative acceleration?

 

 

Explain why you chose the answer you did:

 

 

 

 

5. True or False: A position time graph must be horizontal to have an acceleration of
zero.
Explain why you chose the answer you did:

 

 

 

 

6. A car moves with the motion described by the distance vs. time graph below.
Draw the same car’s motion on the corresponding velocity vs. time and
acceleration vs. time graphs.

 

 

 

 

 

 

63

7. A car moves with the motion described by the velocity vs. time graph below.
Draw the same car’s motion on the corresponding distance vs. time graph and
acceleration vs. time graphs.

v / d a

 

t t t

 

 

 

8. A car drives at a constant velocity for 2 seconds, then Slows to a stop in another 2
seconds. Draw this motion into the graph below.

 

 

64

9. Below is a graph Of a ball’s motion. Describe the motion occurring.

 

Position (m)

 

 

 

Time (s)

 

 

 

 

 

65

10. A car is traveling along a road. Its velocity is recorded as a function of time and is
shown in the graph below.

 

I) v .73 v e - r v .

Velocity (m/s)

 

 

 

 

4

0 2 I I I ‘9 U II 16 II it)

Time (s)

 

During which intervals is the car accelerating? Choose all the answers that apply.

between 0 and 3 seconds

for a brief instant at 3,8,13 and 17 seconds
between 3 and 8 seconds

between 8 and 13 seconds

between 13 and 17 seconds

between 17 and 20 seconds

5‘5.“ 9'9 9‘!”

Explain why you chose the answer you did:

 

 

 

 

66

Appendix B2

TRANSLATIONAL MOTION AND KINEMATICS

Multiple Choice:
1. The acceleration of a stone thrown upward is:

a. greater than that of a stone thrown downward
b. the same as that of a stone thrown downward

c. smaller than that of a stone thrown downward

(1. zero until it reaches the highest point in its motion

2. If you have a positive velocity and a negative acceleration, what will the resulting
motion be?

free fall towards the earth
speeding up in the + x direction
slowing down in the - x direction
speeding up in the — x direction
slowing down in the + x direction

rue-99‘s»

3. A ball is thrown upward with a speed of 20 m/S. It will continue to rise for about

a.ls b. 25 c.3s d.4s

4. About how long after it was thrown will the ball in the previous question reach the
release point?

a.2s b.4s c.8S d.l6s

5. On a position time graph, what represents velocity?

a. speed b. m/s c. area d. slope

67

6. A package is released from a hovering helicopter and it takes 9 s to reach the ground.
If there were no air resistance, the package’s final speed would be

a. -9m/s b. -9.8 m/s c. -88 m/s d. -98 m/s

7. If you have a negative velocity and a negative acceleration, what will the resulting
motion be?

Slowing down in the + x direction
Speeding up in the + x direction
Slowing down in the — x direction
Speeding up in the — x direction

9.0 9‘9

8. If a ball rolls downhill with a constant acceleration of 4 m/SZ. If it starts fiom rest, its
Speed at the end of3 sis:

a. 3 m/S b. 4m/s c. 12 m/s d.18m/s

9. What is the average acceleration of the graph shown below?

a. 0.6 m/s2 b. 0.5 m/S
c. 1.0 m/s d. 0.5 m/s2

68

>1
o

 

F"
o

 

 

.V‘
o

:P‘
o

 

9’
o

 

Velocity (m/S)

 

 

I"
o

 

l—5
O

 

 

 

 

 

 

 

O 2.0 4.0 6.0 8.0 10.0
Elapsed time (s)

10. What is the total displacement for the first 2 seconds Of the graph from #9?
a. 3.0 m b. 2.0 m

c. 1.25m d. 1.5m

11. Velocity measures all of the following EXCEPT

The speed of an object

The total displacement of an Object

The direction of an object’s motion
The displacement for each time interval

9.0 9:2»

69

12. Which of the following position vs. time graphs shows constant

positive acceleration?

a A ll
X X X j X
l l

A B C D

 

 

 

13 . Which of the following velocity vs. time graphs shows constant

negative acceleration?

'14 '14. Lb

A B C D

70

14. A car is traveling along a road. Its velocity is recorded as a function of time and is
shown in the graph below.

I} r v v v v

 

Velocity (m/s)

 

 

 

 

0 2 I Q B 10 I] II 16 Is 3‘]

Time (3)

During which intervals is the car accelerating? Choose all the answers that apply.

between 0 and 3 seconds

for a brief instant at 3,8,13 and 17 seconds
between 3 and 8 seconds

between 8 and 13 seconds

between 13 and 17 seconds

between 17 and 20 seconds

arr-macro

True or False

15. A position vs. time graph must be a horizontal line to have an acceleration of zero.

16. A reference point refers to an object’s speed.

71

Problems: Show all your work for full credit!

1 . A motorcycle traveling at 10 m/s accelerates at a constant rate of 3.5 rn/s2 over 96 Hi.
What is its final velocity?

2. From the moment a 52 m/s fastball touches the catcher’s mitt until it is completely
stopped takes 0.021 seconds. Calculate the average acceleration of the ball being caught.

3 . A racecar starts from rest and is accelerated uniformly to 41 m/S in 9.0 s. ‘

a. What is the car’s displacement?

b. Draw a position vs. time graph of the car’s motion.

4. Graph velocity vs. time & acceleration vs. time of the following position vs. time
graph.

x (m)

 

 

Time (s)

72

5. Graph position vs. time & acceleration vs. time of the following velocity vs. time
graph.

v (m/s)

 

 

Time (s)

6. A camera is accidentally dropped from the edge of a cliff and 13 S later hits the bottom.
a. How fast was it going just before it hit the ground?

b. How high is the cliff?

7. A rock is thrown vertically upward with a velocity of 21 m/s from the edge of a bridge
30 m above the river.

a. What is the rock’s velocity just before it hits the water?

b. How long does the rock stay in the air?

73

8. Below is a graph of a ball’s motion. Describe the motion occurring.

 

Position (m)

 

 

 

O 5 10

Time (s)

74

1.

Appendix B3

Projectile Motion Pretest

Projectile motion consists of two components that are independent of each other.
(True or False)
Explain why you chose the answer you did:

 

 

 

What is the path of a projectile?

a. A wavy line

b. A parabola

c. A hyperbola

d. Projectiles do not follow a predictable path.
Explain why you chose the answer you did:

 

 

 

. A football follows the trajectory as indicated below. Draw in the horizontal and

vertical velocity vectors at each point indicated. Remember, vectors have two
components, magnitude (length) and direction.

75

4. As a projectile flies through the air (disregard air resistance), what can you say of
the horizontal velocity?
a. Increases
b. Decreases
c. Stays the same
(I. Decreases, then increases.
Explain why you chose the answer you did:

 

 

 

 

5. If a ball is thrown upward, and then falls to the ground (disregard air resistance),
what can you say of the vertical velocity?

a. Increases, then decreases

b. Decreases, then increases

c. Stays the same

d. Decreases
Explain why you chose the answer you did:

 

 

 

 

6. Which of the following cannot be considered a projectile?
a. an airplane taking off
b. a tennis ball lobbed over a net
c. a frog jumping from land into the water
d. a bullet fired from a gun
Explain why you chose the answer you did:

76

7. A bowling ball accidentally falls out of an airplane as it flies horizontally from
Detroit to Miami. As seen from the ground, which path would the bowling ball
most closely follow? (circle one)

\ “WWW—WW)
, ...A o _._....... fluuuouolcilooollt I

   

 

 

a. b. c. d.

Explain why you chose the answer you did:

 

 

 

 

8 . A bullet is fired horizontally from a pistol, and another bullet is dropped
simultaneously from the same height. If air resistance is neglected, which bullet
hits the ground first? As always, disregard air resistance. Explain your
reasoning! Draw pictures if they help to explain.

9. If a rock is dropped from the top of a sailboat’s mast, will it hit the deck at the
same point whether the boat is at rest or in motion at a constant velocity? As
always, disregard air resistance. Explain your reasoning. Draw pictures if they
help to explain.

77

10. Does a wad of gum dropped out of the window of a moving car take longer to
reach the ground than one dropped from the same height from a car at rest? As
always, disregard air resistance. Explain your reasoning. Draw pictures if they
help to explain.

78

Appendix B4

World Series of Projectile Motion

1. Projectile motion consists of two components that are dependent on each other.

(T or F)
2. What is the path of a projectile?

a wavy line

a parabola

a hyperbola

Projectiles do not follow a predictable path.

999‘!”

3- As a projectile flies through the air (disregard air resistance), what can you say of the
horizontal velocity?

a. Increases

b. Decreases

c. Stays the same

(I. Decreases, then increases.

4. Which of the following can be considered a projectile?

a. A child swinging on a swing at the playground.
b. A golf ball sitting on a tee.
c. A helium balloon.

d. A volleyball in freefall after being hit by a player.

5 . A hawk is carrying a mouse it has just caught. It accidentally drops the mouse (don’t
Worry, the mouse is okay) from a height of 100m. The mouse lands a horizontal distance
0f 253m from where it was released.

a. Draw a diagram showing the hawk’s direction as well as the trajectory of the
mouse as it flies through the air.

b. How fast was the hawk moving when it dropped the mouse?

6- At baseball practice, Verlander attempts to throw two baseballs at once. He manages
to throw the first, and launches it horizontally. Unfortunately at the same time he

releases the first ball, the second ball falls out of his hand and straight to the ground.
(Verlander is 1.95 m tall)

a. How long does it take the first ball to hit the ground?
b. How long does it take the second ball to hit the ground?

c. Describe if and how the vertical velocity of the first ball changes as it moves
through the air.

79

7 . A track star in the long jump goes into the jump at 12m/s and launches herself at 200°
above the horizontal.

a.

9.09"

e.

Draw a velocity vector analysis, labeling v, vx, and vy at at least 3 points on the
trajectory.

How far did she travel in the horizontal?

What is her hangtime?

Calculate her highest height.
Calculate her final velocity in both the x and y direction.

8. If a rock is dropped from the top of a sailboat’s mast, will it hit the deck at the same
point whether the boat is at rest or in motion at a constant velocity? Explain your
reasoning. Draw pictures if they help to explain.

80

Appendix B5

Momentum Pre-test

1. Two billiard balls of equal mass, traveling at same speed but in opposite
directions, collide. What happens?

a. The balls bounce off of each other, but now they are moving at different
Speeds then they were before the collision.

b. The balls bounce off of each other, and continue to travel at the same
speed they were before the collision.

c. One ball comes to rest and the other bounces off and continues at the same
speed as it was previously.

(1. Both balls come to rest.

Explain why you chose the answer you did:

 

 

 

2- Two objects with different masses collide and bounce back after an elastic
collision. Before the collision the two objects were moving at velocities equal in
magnitude but opposite in direction. After the collision,

a. the less massive object has gained momentum.
b. the more massive object has gained momentum.
c. both objects had the same momentum.

d. both objects lost momentum.

Explain why you chose the answer you did:

 

 

81

3. Which of the following statements about the conservation of momentum is NOT
correct?

a.

b.

C.

d.

Momentum is conserved for a system of objects pushing away from each
other.

Momentum is not conserved for a system of objects in a head-on collision.
Momentum is conserved when two or more interacting objects push away
from each other.

The total momentum of a system of interacting objects remains constant
regardless of forces between the objects.

Explain why you chose the answer you did:

 

 

 

4. A bowling ball moving rapidly strikes a bowling pin that is stationary. After the
collision, the bowling ball continues to move in the same direction, but at a much
slower speed. The bowling pin

a.

b.

C.

d.

travels at the same speed as the ball was moving.
travels at a Slower speed than the ball was moving.
travels at a faster speed than the ball was moving.
does not move.

Explain why you chose the answer you did:

K

\

 

 

5. Two cars collide and stick together. If car #1 was moving rapidly and car #2 was
stationary, what is their combined speed after?
a. Faster than car #1 ’3 original speed.
b. Slower than car #1 ’3 original speed.
c. Same as car #1 ’3 original speed.
(1. Zero

EJ'iplain why you chose the answer you did:

\

\

82

6. You are on rollerblades, holding a medicine ball. Both you and the ball are not
moving. If you throw the ball forward,
a. you move backward
b. you move forward
c. you don’t move at all
(I. Nonsense, why would I ever hold a medicine ball while on rollerblades.

Explain why you chose the answer you did:

 

 

 

 

7. In an elastic collision between two objects with unequal masses,

the total momentum of the system will increase.

the total momentum of the system will decrease.

the kinetic energy of the system will decrease.

the momentum of one object will increase by the amount that the
momentum of the other object decreases.

.o-e 9‘s»

EXplain why you chose the answer you did:

\
x
x

x

8. Two snowballs, one with a mass of 0.4kg traveling east and the other with a mass
of 0.75kg traveling west, collide head on and combine (stick together) to form a
single snowball. The initial speed of each is lSm/s. Straight line motion. Draw a

before and after picture of the collision and label.

83

9. Why are seatbelts more important to wear in cars than buses?

10. “Follow-through” is an important concept in when hitting a baseball with a bat.
This means you should try to keep the bat in contact with the ball for as long as
possible. Why is this an effective technique?

84

Appendix B6

“Mo-better-mentum” Last Mechanics Quiz!

. The change in an object’s momentum is equal to
a. the product of the mass of the object and the time interval.
b. the product of the force applied to the object and the time interval.
c. the time interval divided by the net external force.
(I. the net external force divided by the time interval.
. Two objects with different masses collide and bounce back after an elastic
collision. Before the collision, the two objects were moving at velocities equal in
magnitude by opposite in direction. After the collision,
a. the less massive object had gained momentum.

b. the more massive object has gained momentum.
c. both objects had the same momentum.
(I. both objects lost momentum.
. Which of the following statements about the conservation of momentum is NOT
correct?
a. Momentum is conserved for a system of objects pushing away from each
other.
b. Momentum is not conserved for a system of objects in a head-on collision.
c. Momentum is conserved when two or more interacting Objects push away
from each other.
(I. The total momentum of a system of interacting objects remains constant
regardless of forces between the objects.
. The impulse experienced by a body is equivalent to the body’s change in

a. velocity c. momentum
b. kinetic energy (I. force
. An astronaut with a mass of 70kg is outside a space capsule when the tether line
breaks. To return to the capsule, the astronaut throws a 2kg wrench away from
the capsule at a speed of 14m/s. At what Speed does the astronaut move toward
the capsule.

a. 5.0m/s c. 3.5m/s

b. 0.4m/s d. 7.0m/s
. A bullet with a mass of 5.00 x 10'3 kg is loaded into a gun. The loaded gun has a
mass of 0.52kg. The bullet is fired, causing the empty gun to recoil at a speed of
2.1m/s. What is the speed of the bullet?

a. 48m/s c. 120m/s

b. 220m/s d. 360m/s

85

10.

11.
12.

13.

Two objects stick together and move with the same velocity after colliding.
Identify the type of collision.

a. elastic c. inelastic

b. perfectly elastic d. perfectly inelastic

A bowling ball with a mass of 7.0kg strikes a pin that has a mass of 2.0kg. The
pin flies forward with a velocity of 6.0m/s, and the ball continues forward at
4.0m/s. What was the original velocity of the ball?

a. 4.0m/s c. 6.6m/s

b. 5.7m/s d. 3.3m/s

In an elastic collision between two objects with unequal masses,
a. the total momentum of the system will increase.
b. the total momentum of the system will decrease.
c. the kinetic energy of the system will decrease.
d. the momentum of one object will increase by the amount that the
momentum of the other object decreases.
Two billiard balls of equal mass, traveling at same speed but in opposite
directions, collide. What happens?
a. The balls bounce off of each other, but now they are moving at different
Speeds then they were before the collision.
b. The balls bounce off of each other, and continue to travel at the same
speed they were before the collision.
c. One ball comes to rest and the other bounces off and continues at the same
speed as it was previously.
d. Both balls come to rest.
What is the momentum of a 1500kg car traveling at 115km/h?

A ball with a mass of 0.15kg and a velocity of 5.0m/s strikes a wall and bounces
straight back with a velocity of 3.0m/s. What is the change in momentum of the
ball?
An egg has a mass of 46g and is thrown at a towel so it doesn’t break. If the egg
hits the towel at a speed of 20m/s and has a At of 0.8s,

a. What is the average force on the egg?

b. What is the impulse?

0. Why does the towel keep the egg from breaking, whereas a wall might

not?

86

14. Two snowballs, one with a mass of 0.4kg traveling east and the other with a mass
of 0.75kg traveling west, collide head on and combine (stick together) to form a
Single snowball. The initial speed of each is 15m/s. Straight line motion.

a.

sop-.09:

f.

Draw a before and after picture of the collision and label.
What type of collision is this?

What is the new velocity?

Is momentum conserved?

Is total energy conserved?

What type of energy is not conserved?

15. Why are seatbelts more important to wear in cars than buses?

87

Appendix B7
PHYSICS I A FINAL

Multiple Choice

Identifi/ the letter of the choice that best completes the statement or answers the question

 

1. 2 km/hr = m/s
3. 0.6 m/s c. 2 m/s
b. 0.556 m/s (1. 7.2 m/S
2. Acceleration is
a. displacement. c. velocity.

b. the rate of change of displacement.

d. the rate of change of velocity.

 

3. When velocity is positive and acceleration is negative, what happens to the
object’s motion?

a. The object slows down.

c. Nothing happens to the object.

b- The object speeds up. d. The object remains at rest.

88

 

>1
o

 

 

9‘
o

9‘
o

 

:9
o

 

9°
0

 

Velocity (m/S)

 

E"
o

 

2"
o

 

 

 

 

 

 

 

o 2.0 4.0 6.0 8.0 10.0
Elapsed time (S)

4. What does the graph above illustrate about acceleration?
The acceleration is constant.

The acceleration is zero.

The acceleration decreases.

There is not enough information to answer.

89

.9
o

 

9‘
o

 

9'
o

 

.p.
O
53’
\

 

/\ /

 

Velocity (m/s)

 

 

r"
o

_§§\E’:
/
(\

 

 

 

 

 

 

 

0 2.0 4.0 6.0 8.0 10.0
Elapsed time (s)
5. What does the graph above illustrate about acceleration?

a. The acceleration varies.
b. The acceleration is zero.
c. The acceleration is constant.

(I. The acceleration increases then becomes constant.

6. A toy car is given an initial velocity of 5.0 m/s and experiences a constant
acceleration of 2.0 m/32. What is the final velocity after 6.0 s?

a. 10.0m/s c. 16m/s
b. 12m/s d. l7m/s

90

7. A curious kitten pushes a ball of yarn at rest with its nose, displacing the
ball of yarn 17.5 cm in 2.00 8. What is the acceleration of the ball of yarn?

a- 11 .0 cm/s2 C- 14.4 cm/s2
b. 2 d 2
8.75 cm/s ° 4.38 cm/s
8. Acceleration due to gravity is also called
a. negative velocity. c. free-fall acceleration.

b. displacement. d. instantaneous velocity.

9.

 

A rock is thrown straight upward with an initial velocity of 24.5 m/s where

the downward acceleration due to gravity is 9.81 m/sz. What is the rock's displacement
after 1.00 s?

a. 9.81m c. 24.5m

b. 19.6 m d. 29.4 m

x 10. A coin released at rest from the top of a tower hits the ground after falling
1.5 8. What is the speed of the coin as it hits the ground? (Disregard air resistance. g =
9.81 m/sz.)

a. 15m/s c. 3lm/S

b- 21 m/s (1. 39m/s

91

1 1. A rock is thrown downward from the top of a cliff with an initial speed of
12 m/s- If the rock hits the ground after 2.0 3, what is the height of the cliff? (Disregard
air resistance. g = 9.81 m/sz.)

 

a. 22 m c. 44 m
b. 24 m d. 63 m

12. When there is no air resistance, objects of different masses
a.

fall with equal accelerations with similar displacements.

13. fall with different accelerations with different displacements.
0- fall with equal accelerations with different displacements.
(I.

fall with different accelerations with similar displacements.

\ 13. Which of the following is a physical quantity that has both magnitude and
direction?

a. vector 0. resultant

b- scalar (1. frame of reference

 

14. A lightning bug flies at a velocity of 0.25 m/s due east toward another
lightning bug seen off in the distance. A breeze blows on the bug at a velocity of 0.25 m/s
from the west. What is the resultant velocity of the lightning bug?

a. 0.50 m/s c. 0.75 m/s

b. 0.00 m/s (1. 0.25 m/s

92

l 5. A skateboarder rolls 25.0 m down a hill that descends at an angle of 20.0[1
with the horizontal. Find the horizontal and vertical components of the skateboarder's
displacement.

a. 8.55 m; 23.5 m c. 23.5 m; 73.1 m

b. 23-5 m; 8.55 m d. 73.1 m; 26.6 m

 

16. A stone is thrown at an angle of 30.08 above the horizontal from the top
edge of a cliff with an initial speed of 12 m/S. A stopwatch measures the stone’s

trajectory time from the top of the cliff to the bottom at 5.6 3. What is the height of the
cliff? (Disregard air resistance. g = 9.81 m/sz.)

a. 58m c. 120m

b. 150m d. 180m

\ 17. A model rocket flies horizontally off the edge of the cliff at a velocity of

50.0 nr/s. If the canyon below is 100.0 m deep, how far from the edge of the cliff does the
mOdel rocket land?

a. 112m c. 337m
b- 225m d. 400m

 

18. A firefighter 50.0 m away from a burning building directs a stream of
Water from a fire hose at an angle of 30.00 above the horizontal. If the velocity of the
Stream is 40.0 m/s, at what height will the stream of water strike the building?

a. 9.60m c. 18.7m

b. 13.4m (1. 22.4m

93

1 9. What causes a moving object to change direction?

a. acceleration c. inertia

b. velocity (1. force

 

20. In the free-body diagram shown above, which of the following is
the gravitational force acting on the car?

a. 5800N c. 14 700N

b. 775N d. 13 690N

 

 

94

21. In the free-body diagram shown above, what is the net force and direction
on the balloon?

a. 1212N@118° c. 1070N@62°

b. -570N@118° d. 1212N@62°

22. Which of the following is the tendency of an object to maintain its state of
motion?

a. acceleration c. inertia
b. velocity (1. force
23. A Sled is pulled at a constant velocity across a horizontal snow surface. If

a force of 8.0 l] 101 N is being applied to the sled rope at an angle of 53 D to the ground,
what is the force of friction between the sled and the snow?

a. 48N c. 83N

b. 42N d. 64N

24. Which statement about the acceleration of an object is correct?

___-—

a. The acceleration of an object is directly proportional to the net external force
acting on the object and inversely proportional to the mass of the object.

b. The acceleration of an object is directly proportional to the net external force
acting on the object and directly proportional to the mass of the object.

c. The acceleration of an object is inversely proportional to the net external force
acting on the object and inversely proportional to the mass of the object.

(I. The acceleration of an object is inversely proportional to the net external force
acting on the object and directly proportional to the mass of the object.

95

25. Which of the following does NOT describe a condition for a conservative

force?
a. The net work is = 0 0. decrease PE of the object
b. Internal forces = 0 d. isolated system

26. The statement by Newton that for every action there is an equal but
opposite reaction is which of his laws of motion?

a. first c. third

b. second d. fourth (this is not the answer!)

27. A sled weighing 1.0 X102 N is held in place on a frictionless 20.0° slope

by a rope attached to a stake at the top. The rope is parallel to the slope. What is the
normal force of the slope acting on the sled?

 

a. 94N c. 37N

b. 47N d. 34N

_ 28. A crate is carried in a pickup truck traveling horizontally at 15.0 m/s. The
truck applies the brakes for a distance of 28.7 m while stopping with uniform
acceleration. What is the coefficient of static friction between the crate and the truck bed
if the crate does not slide?

a. 0.400 c. 0.892
b. 0.365 d. 0.656

96

29. An Olympic skier moving at 20.0 m/S down a 30.0°slope encounters a
region of wet snow and slides 145 m before coming to a halt (stopped). What is the
coefficient of fiiction between the skis and the snow?

a. 0.540 c. 0.116
b. 0.740 d. 0.470

30. A force does work on an object if a component of the force
a. is perpendicular to the displacement of the object.
b. is parallel to the displacement of the object.

c. perpendicular to the displacement of the object moves the object along a path that
returns the object to its starting position.

d. parallel to the displacement of the object moves the object along a path that returns
the object to its starting position.

31. A hill is 100 m long and makes an angle of 12° with the horizontal. As a
50 kg jogger runs up the hill, how much work does the jogger complete against gravity?

a. 50 000 J c. —10 000 J
b. 10 000 .1 d. 0.0 J

32. A construction worker pushes a wheelbarrow 5.0 m with a horizontal force
of 50.0 N. How much work is done by the worker on the wheelbarrow?

a. 10.1 c. 250.1
b. 1250.1 (1. 55.1

33. If both the mass and the velocity of a ball are tripled, the kinetic energy of
the ball is increased by a factor of

a. 6. c. 9.

b. 3. d. 27.

97

34. Which of the following energy forms is associated with an object due to
its position?

a. potential c. total

b. positional d. kinetic

_ 35. A 40.0 N crate is pulled up a 5.0 m inclined plane at a constant velocity. If
the plane is inclined at an angle of 37° to the horizontal and there is a constant force of
friction of 10.0 N between the crate and the surface, what is the net gain in potential
energy by the crate?

a. 120.1 c. 210.1

b. —l20.1 d. —2IOJ

36. An 80.0 kg climber with a 20.0 kg pack climbs 8848 m to the top of
Mount Everest. What is the climber’s potential energy?

a- 6.94 [11061 C- 2.47 [11061

b- 4.16 [31061 d- 1.00 E1106J

37. A pole vaulter clears 6.00 m. With what velocity does the vaulter strike

the mat in the landing area? (Disregard air resistance. g = 9.81 m/sz.)

a. 2.70 m/s c. 10.8 m/s
b. 5.40 m/s d. 21.6 MS

98

38. True or False: Kinetic energy is conserved during an elastic collision.

a. True b. False

39. A horizontal force of 2.00 X 102 N is applied to a 55.0 kg cart across a

10.0 m level surface, accelerating it 2.00 m/sz. Using the work—kinetic energy theorem,
find the force of friction that slows the motion of the cart? (Disregard air resistance. g =

9.31 m/sz.)

a. 110N c. 80.0N

b. 90.0N d. 70.0N

40. Which of the following is the rate at which energy is transferred?

a. potential energy c. mechanical energy

b. kinetic energy d. power

41. What is the average power output of a weight lifter who can lift 250 kg,
2.0 m in 2.0 s?

a. 5.0 x102 w c. 4.9 kW

b. 2.5 kW d. 9.8 kW

42. What is the gravitational force between two trucks, each with a mass of
2.0 x 104 kg, that are 2.0 m apart? (G = 6.673 x 10‘” NmZ/kgz)

 

3- 5.7 x 10‘2 N C- 6.7 x 10‘3 N

b- 1.3x10WN d- 1.2x10WN

99

43. Two small masses that are 10.0 cm apart attract each other with a force of
10.0 N. When they are 5.0 cm apart, these masses will attract each other with what force?

(G = 6.673 x 10‘11 Nmz/kgz)
a. 5.0 N c. 20.0 N

b. 2.5N d. 40.0N

44. A mass attached to a spring vibrates back and forth. At the equilibrium
position, the

a. the acceleration reaches a maximum. c. net force reaches a maximum.

b. velocity reaches a maximum. (1. velocity reaches zero.

45. If a force of 50 N stretches a Spring 0.10 m, what is the spring constant?
a. 5 N/m c. —5 N/m
b. 500 N/m (1. —500 N/m

46. A 0.20 kg block rests on a frictionless level surface and is attached to a
horizontal spring (k = 40 N/m). The block is initially displaced 4.0 cm from the
equilibrium pt. and then released. What is the speed of the block when it passes through
the equilibrium pt. ?

 

a. 2.1 m/s b. 1.6 m/s c. 1.1 m/s d. 0.57 111/5

47. A spring with a spring constant of 500 N/m is compressed 4.0 cm. What
is the potential energy stored?

 

a. 80001 c. 0.4.1

b. 4000] d. 0.81

100

48. A wheel has a circumference of 2.3m and rotates at 1.8 rad/sec. Find the
magnitude of centripetal acceleration that a 20g object will experience on the outside of
the wheel.

 

a. 0.233 m/sz c. 11.66 m/s2
b. 2.33 m/s2 d. 1.16 m/s.2

49. The centripetal force (in Newtons) required to cause a 4.0 kg object to
move at 0.06 m/s in a circle of radius 1.0m is:

 

 

 

a. 0.024 c. 0.031
b. 0.014 a. 0.24
T
60° ,
pin ¢ \1

 

1 20 N
50. A uniform horizontal beam with a length of 6.0 m and a weight of 120 N is attached
at one end to a wall by a pin connection SO that the beam can rotate. The opposite end of
the beam is supported by a cable attached to the wall above the pin. The cable makes an
angle of 600° with the beam. What is the tension in the cable needed to maintain the
beam in equilibrium?
a. 35 N C. 6.0 x 101 N

b. 69N d. 120N

101

51. Which of the following statements is correct?
a. The farther the center of mass of an object is from the axis of rotation, the less
difficult it is to rotate the object.

b. The farther the center of mass of an object is from the axis of rotation, the smaller
the object’s moment of inertia is.

c. The farther the center of mass of an object is from the axis of rotation, the greater
the object’s moment of inertia is.

d. The farther the center of mass of an object is from the axis of rotation, the greater
the object’s moment of inertia is, but the less difficult it is to rotate the object.

52. Centrifugal force

points inward toward the center of a circular path

points outward away from the center of the circular path
points along the tangent to the circle

isn’t really a force

9-99‘9

53. A 13g object is attached to a 0.93 m string. The object is swung in a horizontal
circle, making one revolution in 1.18 sec. Find the tension force exerted by the string.
a. 1.8N c. 0.34N

b. 34N d. 18N

54. A child with a weight of 4.50 x 102 N sits on a seesaw 0.60 m from the axis of
rotation. How far from the axis of rotation on the other side should a child with a weight

of 6.00 x 102 N sit so the seesaw will remain balanced?

a. 0.30m c. 0.45m

b. 0.40m (1. 0.50m

102

55. After colliding, objects are deformed and lose kinetic energy. Identify the type of
collision.

a. elastic b. perfectly inelastic
c. inelastic d. perfectly elastic

56. A 0.4 kg mass, attached to the end of a 0.75 m string, is whirled around in a circular
horizontal path. If the maximum tension that the string can withstand is 450 N, then what
maximum speed can the mass have if the string is not to break?

a. 370 m/S b. 22 m/s c. 19m/s d. 29 m/s

57. A satellite is in a circular orbit about the earth at a distance of one earth radius above
the surface. What is the Speed of the satellite? Mass = 5.98 x 1024kg, radius = 6.4 x

106m

a. 2600 m/S b. 4800 m/s c. 5600 m/s (1. 16800 m/s

58. During a snowball fight two snow balls with mass of 0.4 kg and 0.6 kg, respectively,
are thrown in such a manner that they meet head-on and combine to form a single mass.
The magnitude of the initial velocity for each is 15 m/s. What is the speed of the 1.0 kg
mass immediately after the collision?

a. zero b. 3m/S c. 6m/S d. 9m/S

59. A physics student throws a 0.15 kg rubber ball down onto the floor. The ball’s speed
just before impact is 6.5 m/s, and just after is 3.5 m/s. If the ball is in contact with the

floor for 0.025 sec., what is the magnitude of the average force applied by the floor
on the ball?
a. 60N b. 133 N c. 3.0N d. 3.5N

103

60. In order for an object to be in equilibrium:

a. all forces must equal zero c. all forces must be static
b. the rotational and translational velocities must be constant d. all torques must
equal zero

61. A mass on a spring vibrates in simple harmonic motion at an amplitude of 8.0 cm.
If the mass of the object is 0.20 kg and the spring constant is 130 N/m, what is the
frequency?

a. 1.5 Hz c. 4.0 Hz

b. 8.7 Hz d. 1.6 Hz

62. What is the period of a 4.12 m long pendulum?
a. 2.01 S c. 4.07 s
b. 3.11 S d. 9.695

63. On the planet Xenos, an astronaut observes that a 1.00 m long pendulum has a
period of 1.50 S. What is the free-fall acceleration on Xenos?

a-4.18m/s2 c WSW?

b w2w¥ d msmf

64. A water bed that is 1.5 m wide and 2.5 m long weighs 1055 N. Assuming the
entire lower surface of the bed is in contact with the floor, what is the pressure the bed
exerts on the floor?

a. 250 Pa c. 270 Pa

b. 260 Pa (1. 280 Pa

104

65. Each tire of an automobile has an area of 0.026 m2 in contact with the ground.

The weight of the automobile is 2.6 l] 104 N. What is the pressure in the tires?
6 5
a. 3.1x10 Pa C: 2.5 x10 Pa

b- 6.5x103Pa d- 1.0x106Pa

105

Appendix C1
Moving Man Simulation Homework
Procedure: Do the following activity using this website:
http://www.colorado.edu/physics/phet/simulations-basehtml
Then click on “The Moving Man”
Click “Run Now”

1. After “The Moving Man” is open, play with the controls a bit to get the hang of the
program.

2. By changing the values of x,v, and/or a, you cause the man to move back and forth
and observe what shows up on the graphs. The simulation also allOws you to move
the man by dragging him... however, this gives “messy” graphs so be sure to type in
the values instead!

3. Using the axis provided below make Sketches of d vs. t and v vs. t graphs for the
actions described next to each axis. As you work through the situations, pay attention
to the acceleration vs. time graph, even though you are not asked to graph it.

A man moving from 0 to 10 m at a slow steady pace.

 

 

 

 

106

A man moving from 0 to 10m at a fast pace

 

 

 

A man standing still at 4m

 

 

 

 

A man moving from 0 to 10m at a fast pace then moving back to 0 at a Slow pace.

 

 

 

 

107

A man moving from 0 to -10m at a fast pace then moving back to O at a slow pace.

 

 

 

 

A man moving from 10 to Om at a fast pace.

 

 

After observing the acceleration vs. time graphs for each of the above activities, what did
you notice?

What kind of motion do you need to have so that the acceleration vs. time graphs is not a
“flatline”?

108

Apply what you learned:

Look at the distance vs. time graph below. Draw the corresponding velocity vs. time and
acceleration vs. time graphs.

 

.J \\

 

 

 

 

 

109

Appendix C2

Graphing Motion Notes

 

 

** translate d vs. t graph into v and a vs t graphs. Below are graphs of the same motion,
but in v and a.

 

 

 

 

+
V

T
+
A Both lines are at zero
dvs.t vvs.t avs.t

 

110

Slope

V

 

A

“Demonstration: Using motion detector and graphing motion program from Vernier, I
Show students the graphs, and call some up to move around in front of a (1 vs. t graph and
a v vs. t graph for the class to watch. I then bring up some of the pre-made graphs, which

get progressively harder. I ask students to volunteer to try to match the graphs, while the

Area

others can help them out by calling out directions.

Examples:

(1 (speeding up) .‘W

O"
-1

 

 

 

 

 

 

 

 

 

 

t

 

both v and a lines are at 0

111

 

(slowing down)

‘—
’-
"
I

 

 

v
’I
I
I
I
I
l
l
t
Dropping an object
+
v

 

 

Move further from the origin = graph moves up

Stop — graph straight

Move closer to origin = graph moves down

 

 

 

 

 

 

 

 

 

a
t
+
a
l ........
this Should be -9.8m/s
+
l- .........
a
‘ t

 

Appendix C3
Graphing Motion Demonstration
Equipment used:

Vernier software
LabPro

Motion Detector
Computer
Description:

The instructor displays a graph for the class to see. The class is asked to imagine how
they would need to move in order to recreate this graph. Then volunteers are asked to try
to do this. Several volunteers are asked to try each of four graphs in that are premade in
the Vernier software. If student volunteers struggle, the class is allowed to help the
student to recreate the graph.

113

Appendix C4

Graphing Motion Worksheet

1. Describe the motion that is occurring in the v vs. t graph at each letter.
2. Fill in the corresponding x vs. t graph and a vs. t graph.

3. Confirm that your descriptions match your graphs.

 

 

 

 

 

 

114

l"

. Describe the motion that is occurring in the x vs. t graph at each letter.

Fill in the corresponding v vs. t graph and a vs. t graph.
Confirm that your descriptions match your graphs.

E

 

 

 

 

 

 

115

Appendix C5

Graphing Motion Lab

Part I : Position vs. Time

1. Place the motion detector so that it points toward an open space at least 4 m long.
2. Open LoggerPro by clicking Start, Programs, LoggerPro. When the program opens,
click File, Open, C drive, Program Files, Vernier software, LoggerPro, Experiment,
Physics with Computers, Experiment 1. Open the experiment file Exp 01a Distance
Graph. A position vs. time graph will appear on the screen.

3. Discuss with your group how you will reproduce the graph shown below, and then try
it.

4. When you get the best graph you can, save to your H drive, and print.

5. Describe how you had to walk in order to reproduce each part of the graph. Write
your description directly on the graph below.

 

 

 

 

Part2: Velocity vs. Time

1. Switch to a velocity vs. time graph. To do this, right click on the graph and click on
graph options. Under axes options, unclick the position box, and click the velocity box.
Then below that, change the top to 2 and the bottom to -2. Click done.

2. Discuss with your group how you will reproduce the graph shown below, and then try
it.

3. When you get the best graph you can, save to your H drive, and print.

4. Describe how you had to walk in order to reproduce each part of the graph. Write your
description directly on the graph below.

116

 

 

 

 

 

 

 

Analysis:

1. What does the slope of a position vs. time graph represent?

2. What type of motion is occurring if the slope of a position vs. time graph is
negative?

3. What type of motion would cause a curved line on a position vs. time graph?

4. Sketch a velocity vs. time graph and acceleration vs. time graph for the position
vs. time graph in part 1.

5. What does the slope of a velocity vs. time graph represent?

6. What type of motion is occurring when the slope of a velocity vs. time graph is
zero?

7. What does the area under a velocity vs. time graph represent?

8. Sketch a position vs. time graph and acceleration vs time graph for the velocity
vs. time graph in part 2.

”Attach the answers to these 8 questions and your two printed graphs to this lab sheet
and turn in with all group member names on it.

117

Appendix C6

Projectile Computer Lab

1. Go to the PHET web site

http://phet.colorado.edu/welygages/simulations-base.html

Go to the Motion Page and start the Projectile Motion simulation.

2. Try using some of the different objects in the pull down menu without air resistance.

3. Now try the different objects with air resistance.

4. What do you notice about all of the projectiles when there is no air resistance?

 

 

 

5. What does air resistance do to a projectile? Why?

 

 

 

6. Why does a bowling ball go farther than a golf ball even though a golf ball has a much
smaller drag coefficient?

 

 

 

118

7. Why does a human go so much farther than a Buick when they have the same drag
coefficient?

 

 

 

8. What things are important to know in order to find out how an objects path will be
changed by air resistance?

 

 

 

9. Move the target to a distance 20 meters from the cannon. With air resistance off and
using the golf ball try each of the following Shots. Be sure to measure and place your
target along the x axis as Shown.

 

Angle 75° 45° 15° 89.4° 9.3°

(degrees)

 

Initial Speed 20 m/sec 14 m/sec 20 m/sec 98 m/sec 24.8 nr/sec
(m/sec)

 

 

Hit or Miss

 

 

 

 

 

 

10. Which angle requires the fastest speed in order to hit the target? Why?

 

 

 

 

11. Which angle requires the Slowest speed to hit the target? Why?

 

 

 

119

12. What do you notice about angles 75° and 15°?

 

 

 

13. If an X appears on the trajectory at each second how long was each shot up in the
air? Which Shot was in the air the longest?

 

 

 

14. How did the shots with the smallest angles go just as far as the Shots that were in the
air the longest?

 

 

 

15. Using the magnifying glass move the target to 490 meters. For the golf ball with no
air resistance fire a Shot with Angle 45° and Initial Speed 69.3 m/sec. This is Trajectory
A.

Without erasing fire a Shot with Angle 75 ° and Initial Speed of 50.7 m/sec. This is
Trajectory B.

These two shapes are called parabolas. Notice the X that appears at each second—the
highest point for each parabola is at 5 seconds. This is called the vertex.

Using the tape measure; measure the height of each vertex and the length of each
trajectory (range).

120

 

Trajectory A Trajectory B

 

Height of Vertex (m)

 

Range (m)

 

 

Duration—seconds in air

 

 

 

16. Why do the X’s get closer together as you get to the top of the parabola?

 

 

 

17. What happens to the Speed of the golf ball as you get closer to the top of the
parabola? Does the horizontal speed change or only the vertical speed?

 

 

l9. Calculate the horizontal speed of each trajectory (hint: use Trig with initial speed and
angle)

 

Trajectory A Trajectory B

 

 

Horizontal Speed (m/sec)

 

 

 

18. For each trajectory, what is the vertical Speed at the vertex of the trajectory? Which
trajectory has the highest total Speed? How can you tell?

 

 

 

121

 

 

Appendix C7

Projectile Motion Notes

Aloud
How many components make up a vector?

- 1. Horizontal-straight line motion
2. Vertical-freefall

-projectile motion combines these two components

-each component is indegndent of the other

-So, it is like solving two problems in one: a freefall and a straight line motion problem
Are they linked by anything?

Do demo with simultaneous ball launcher. Then look at video analyzed to Show
that same time occurs for each.

Time links the two components!

-ie. If you can find the time in the x component, it has the same value in the y
component

Show video of cart moving, Shooting ball upward (or do actual demo)
Written on board

I. Consists of 2 components (x,y) that act independently of each other.
a. Assume no air resistance, remember online simulation.
b. Parabolic shape

11. Vectors of projectiles
"Show video made of projectile, draw diagrams below.

111. Facts to memorize
a. x component:
i. vx stays the same
ii. a=O
iii. time is scalar
b. y component:

122

i. vy changes
ii. =-9.8m/sz
iii. time is scalar
IV. Equations: All kinematic equations apply, but be careful!

**look at demo with beads first at horizontal, then at angle

V. Range Equation: projectile must begin and end on the same plane to use this
equation!

123

Appendix C8

Projectile Motion Demonstrations
“Shoot the Monkey”

A Nerf gun is set up at one end of the classroom while a stuffed animal is set up on the
other end, attached to the ceiling. They are hooked up so that when the trigger on the gun
is pulled, the stuffed animal will automatically be dropped from the ceiling. This setup is
explained to the class. Students are then asked where the instructor needs to aim in order
to hit the monkey. A discussion follows on the mechanics of projectile motion and how
time links the x and y coordinates. The instructor then demonstrates that only by aiming
directly at the stuffed animal and firing, the projectile will hit the stuffed animal. This is
because both the projectile and the stuffed animal fall towards the ground at the same
rate. It does not matter that the stuffed animal is falling straight down while the projectile
is moving forward and falling.

Ball Launcher

The ball launcher allows the instructor to load two metal balls into a projectile launcher at
the same time. One ball is launched horizontally while the other is dropped straight
downward. The launcher releases both balls at the same time. Students can observe that
a horizontal velocity does not have any effect on the time it takes to reach the ground;
both balls hit at exactly the same time.

124

Appendix C9
Projectile Problems

. A ball falls from rest from a height of 490m.
a. How long does it remain in the air?

b. If the ball has a horizontal velocity of 2.00 x 102 m/s when it begins its

fall, what horizontal displacement will it have?

. An archer stands 40.0m from the target. If the arrow is shot horizontally with a
velocity of 90.0m/s, how far above the bull’s-eye must he aim to compensate for
gravity pulling his arrow downward?

. A bridge is 176.4m above a river. If a lead-weighted fishing line is thrown from
the bridge with a horizontal velocity of 22.0m/s, how far has it moved
horizontally when it hits the water?

. A beach ball, moving with a speed of +1 .27m/S, rolls off a pier and hits the water
0.75m from the end of the pier. How high above the water is the pier?

. Carlos has a tendency to drop his bowling ball on his release. Instead of having
the ball on the floor at the completion of his swing, Carlos lets go with ball 0.35m
above the floor. If he throws it horizontally with a velocity of 6.3m/s, what
distance does it travel before you hear a “thud”?

. A discus is released at an angle of 450 and a velocity of 24.0m/s.

a. How long does it stay in the air?

b. What horizontal distance does it travel?

. A shot put is released with a velocity of 12m/s and stays in the air for 2.05.

a. At what angle with the horizontal was it released?

b. What horizontal distance did it travel?

. A football is kicked at 450 and travels 82m before hitting the ground.

a. What was its initial velocity?

b. How long was it in the air?

c. How high did it go?

. A golf ball is hit with a velocity of 24.5m/S at 35.00 above the horizontal.

a. What is the range of the ball?

b. What is the maximum height of the ball?

125

Appendix C10

Projectile Motion Lab

Equipment Needed:

0 Projectile launcher and plastic ball

0 Plumb bob

0 C clamp

0 Meter stick

0 Carbon paper

0 White paper
Purpose:
Theory:

To predict where a ball will land on the floor when it is shot off a table at some angle
above the horizontal, it is necessary to first determine the initial speed (muzzle velocity)
of the ball. This can be determined by shooting the ball horizontally off the table and
measuring the vertical and horizontal distances through which the ball travels. Then the
initial velocity can be used to calculate where the ball will land when it is shot at an
angle.

Setup:

1. Clamp the projectile launcher to a sturdy table near one end.
2. Adjust the angle of the launcher to zero degrees so the ball will be shot off
horizontally.

Part A: Determining the Initial Velocity of the Ball

1. Put the ball into the launcher and cock it to the long range position. Fire one Shot
to locate where the ball hits the floor. At this position, tape a piece of white paper
to the floor. Place a piece of carbon paper (carbon Side down) on top of this paper
and tape it down. When the ball hits the floor, it will leave a mark on the white
paper.

2. Fire 5 shots.

3. Measure the vertical distance (Ay) from the bottom of the ball as it leaves the
barrel (this position is marked on the side of the barrel) to the floor. Record this
distance.

4. Use a plumb bob to find the point on the floor that is directly beneath the release
point on the barrel. Measure the horizontal distance (Ax) along the floor from the
release point to the dot left by the ball. Record. Continue for each remaining
mark left on the paper.

126

Find the average of the 5 distances and record.

Using the vertical distance and the average horizontal distance, calculate the time
of flight and the initial velocity of the ball. Record in a table and Show
calculations in the analysis section.

Part B: Predicting the Range of the Ball Shot at an Angle

. Put the launcher on the floor and adjust the angle between 30 and 70 degrees.

Launch the projectile and locate where the ball hits. Place a box or some books at
that location so that the ball will hit at the same level as the muzzle of the
launcher.

3. Launch the projectile and measure the horizontal distance (range) as it lands on a
piece of white paper and carbon paper.

4. Shoot the ball 5 times at this angle.

5. Repeat for one other angle. (You should have one angle above and one angle
below 45°)

Analysis:

1. Calculate the predicted range of your projectile at the two angles, using initial
velocity from part A. Be sure to include the calculations used to solve for initial
velocity.

2. Calculate the % difference between your predicted value and the resulting average
distance when shot at an angle.

3. Calculate the hang time for all 2 angles.

4. Choose one angle and construct a velocity vector analysis of the projectile path.
For a minimum of 3 points on the path, determine and Show v, vx and vy.

5. How would your results change if we used projectiles of the same size, but with a

larger mass? Explain.

Lab Requirements:

905199;“.909)!‘

Title page

Lab sheet

Purpose

Data fiom part A and part B
Calculations from part A and part B
Analysis questions

3 systematic errors

#4 pg 119 in book

127

Appendix C1 1

PHYSICS MOMENTUM LAB

AIR TRACK SIMULATION.

Go to: (https://www.msu.edu/~brechtjo/physics/airTrack/airTrack.html)

 

This simulation models a basic air track with two blocks.
GENERAL DIRECTIONS:

- Click GO to start. Simulations

- STOP the simulation after the initial collision.
- Final velocity is “current velocity”

- Set a at ‘1’ for ELASTIC COLLISIONS

- Set a at ‘0’ for INELASTIC COLLISIONS

- Reset the simulation after each case.

Part I. ELASTIC COLLISIONS: QUALITATIVE ANALYSIS

DIRECTIONS: After setting the values click on GO and observe what happens AFTER
the collision, then answer the questions indicating your observations regarding the
velocities (how fast, how slow) and direction of each mass.

Elastic Collision Case I. 1111 = 1112

Set the values as: 1nl = 1 kg m2 = 1 kg
v1 = 100 m/S v2: 0 m/S
What happens to Mass 1 (RED)?

 

What happens to Mass 2 (BLUE)?

 

Elastic Collision Case 11. n1l > 1112

Set the values as: m1 = 2 kg m2 = 1 kg
vl= 100 m/S v2=0m/s

What happens to Mass 1 (RED)?

 

What happens to Mass 2 (BLUE)?

128

Elastic Collision Case 111. 1111 < 1112

Set the values as: ml = 1 kg m2 = 2 kg
V1: 100m/S v2=0m/s

What happens to Mass 1 (RED)?

 

What happens to Mass 2 (BLUE)?

 

Part II. COLLISIONS: QUANTITATIVE ANALYSIS

FOR EACH CASE: _
1. Find the values for the FINAL VELOCITIES (v1' and vzf)of each block and record

the values on the tables.
2. Perform your OWN calculations for MOMENTUM (momentum=mass*velocity)

and KINETIC ENERGY (KE=l/2mv2) Showing all your work: equations and answers.

ELASTIC COLLISION I. (Set a at 1)

 

 

 

 

 

 

 

 

 

RED BLOCK BLUE BLOCK
m1 = 3 kg m2 = 2 kg

v1 = 100 m/s v2 = 0 m/s

Initial momentum = Initial momentum =
Initial KE = Initial KE =

V1r = V2: =

Final momentum = Final momentum =
Final KE = Final KE

 

 

129

 

Was momentum conserved? Was KE conserved?

 

Remember: Conserved means total final = total initial

130

 

ELASTIC COLLISION 11. (Set 01 at 1)

 

 

 

RED BLOCK BLUE BLOCK
m1 = 3 kg m2 = 2 kg
v1 = 100 m/s v2 = -50 m/s

 

Initial momentum =

Initial momentum =

 

Initial KE =

Initial KE =

 

1r—

2r—

 

Final momentum =

Final momentum =

 

 

Final KE =

 

Final KE

 

Was momentum conserved?

 

INELASTIC COLLISION I. (Set a at 0)

Was KE conserved?

 

 

 

RED BLOCK BLUE BLOCK
m1 = 3 kg m2 = 2 kg
v1 = 100 m/s v2 = 0 m/s

 

Initial momentum =

Initial momentum =

 

Initial KE =

Initial KE =

 

Vlf’:

Vzr =

 

Final momentum =

Final momentum =

 

 

Final KE =

 

Final KE

 

131

 

 

 

Was momentum conserved? Was KE conserved?
If not, find the loss of KE:

 

INELASTIC COLLISION 11. (Set 0. at 0)

 

 

 

 

 

 

 

 

 

 

 

RED BLOCK BLUE BLOCK
m1 = 3 kg m2 = 2 kg

v1 = 100 m/s v2 = -50 m/s

Initial momentum = Initial momentum =
Initial KE = Initial KE =

V1r = V2r =

Final momentum = Final momentum =
F inal KE = Final KE

Was momentum conserved? Was KE conserved?

 

If not, find the loss of KB:

132

 

 

 

Appendix C12
Momentum Notes
Aloud:

When a baseball is hit, the speed and direction change. . .. Kinematics describe the motion
before and after ........ force and Newton’s laws describe and explain why. . .. Now we
look at force and the duration of the collision

On board:
I. Momentum- vector quantity defined as the product of an object’s mass and
velocity
p=mv “direction of p is that of v units: kg*m/s

the faster you move, the more p you have, and you are harder to stop (ex. Red
Rover)

inertia- mass only -intrinsic property of object
momentum- mass and velocity

ex. Pg 209 #1
m=l46kg v=17m/s
p=(146kg)*(17m/S)=2482kgm/S right
11. Change in momentum takes force and time. . .ex. Semi vs Smartcar rolling down a
hill... which is harder to stop?

Impulse-momentum theory: FAt=Ap or FAtszf'mVi
Small force applied=larger time to stop

F At=impulse

This explains why “follow through” is so important in Sports

Ex. Airbags stop passengers in .753, while dashboard takes .0263 How do the
forces compare?

Both will give the same change in momentum so. ..

133

Fd(.026)=Fa(.75)

Fd=29Fa The dashboard applies a force 29 times greater that the
airbag

Conservation of Momentum

I. The total momentum present in system does not change.

EX- Pbefore=pafter

In order for conservation of momentum to occur, you need an
isolated/closed system (no net external forces such as friction)

*we will always ignore friction in our problems

Momentum is conserved in collisions, as well as when objects push

away from each other.
¢- g C -*

Total momentum of the system is 0 both before and after. . .. Why?

 

 

II. Collisions: total momentum remains constant in any type of collisionll
"total KE is usually not conserved because it is converted into
another energy form when objects collide and deform.

a. Perfectly inelastic collisions: when two objects stick together and
move with a common velocity after colliding
“pay attention to signs indicating direction! (+ and -)
"KE is not conserved in inelastic collisions (KE converted to
sound energy)
"Objects do not keep their original shapes

134

b. Elastic collisions: when two objects collide and return to their
original shapes with no change in total KE.
"After the collision the two objects move separately
”total momentum and KB conserved

Most real-life collisions do not fall into either of these categories-
they fall somewhere in the middle

135

Appendix C13
Conservation of Momentum Demos

Potato and straw: Students are asked to pierce a potato with a drinking straw. If pushed
slowly the straw will be crushed against the potato, but if jabbed quickly, the straw will
pierce the potato. When students discover this, it leads us into a discussion about inertia
and momentum.

Rollerblades and medicine ball: Standing still on rollerblades and holding a medicine
ball, ask students what total momentum of system is... (zero because there is 0 velocity).
Then, throw the medicine ball forward, and you move backward. AS students what
momentum after throwing was (still 0. .. conservation of momentum) why? Because
there was a positive and negative velocity due to opposite directions traveled. Which
moved faster, me or ball? (medicine ball, b/c less mass)

Newton’s Cradle: Momentum is transferred from ball to ball. Drop different numbers
of balls and see how many balls bounce off.

Dropping different sized balls: If dropping a tennis ball and basketball at same time on
top of each other, what happens? Why? What if you drop them with the basketball on
top and the tennis ball on the bottom... why does this happen? (Talk about different
masses)

Collision carts: Use track and various carts with differing masses, for elastic and
inelastic collisions. (Do very briefly, because they will do a lab involving this later)

136

Appendix C14

 

 

 

 

 

 

 

 

 

 

Momentum Lab'

Purpose:
Data:
Mass of cart 1: kg
Mass of cart 2: kg
Elastic Collision

Initial Final
v 1: v I:
v 2= v 2=
1) 1= p 1=
P 2: p 2=
Ptotalz Ptotal=
KE1= KE2=
KE2= KEl=
KEtotal= KBtotal=

 

 

' Is momentum conserved in elastic collisions? Explain using your data.

Is kinetic energy conserved in elastic collisions? Explain using your data.

137

 

Inelastic Collision

 

 

 

 

 

 

 

Initial Final

v l= v 1=

v 2: v 2:

p 2= p 2=

Ptotal= Ptotal=

KE1= KE2=

KE2= KE1=

KEtotaI- KEtotal=

 

 

 

Is momentum conserved in inelastic collisions? Explain using your data.

Is kinetic energy conserved in inelastic collisions? Explain using your data.

138

Determination of unknown mass

 

 

 

 

 

Initial Final
v l= v l=
v 2= v 2=
p 1= p 1=
p 2= p 2=
Ptotal= Ptotalz

 

 

What is the mass of the object? Show work below.

Using the actual mass of the object, find % difference.

List 3 systematic errors.

139

 

Appendix D

Pre and post-tests were all based on a one point per question scale, with a total of 10
questions or 10 points available. Multiple choice questions were either right or wrong (1
or 0 points given) while Short answer questions or questions in which students had to
diagram something could be 0, 0.5, or 1 point based on the completeness and correctness
of their answer.

Scoring Rubrics

Graphing Motion

 

Pretest Question # Scoring Basis

 

1,2,3,4,5,10 Multiple choice:
1 point =correct
0 points: incorrect

 

6, 7 1 point: completely correct

0.5 points: at least '/2 of graph correctly
drawn

0 points: less than '/2 of graph correctly
drawn

 

8 1 point: completely correct (correct slope
and curve to line)

0.5 points: very close to correct (either
slope or curve incorrect)

0 points: both slope and curve incorrect

 

 

9 1 point: description of motion completely
correct

0.5 points: general idea correct, but some
words incorrect such as “forward”
instead of toward or incomplete such as
failing to include a direction

0 points: more than one or two mistakes
in description

 

 

Table 4: Scoring Rubric for Graphing Motion Tests

140

 

 

Projectile Motion

 

Pretest Question #

Scoring Basis

 

1,2,4,5,6,7

Multiple choice:
1 point = correct
0 points = incorrect

 

1 point = all velocity vectors drawn in
correct directions, with arrows
proportionate to velocity

0.5 points = more than half of velocity
vectors drawn correctly, some sizes
correct

0 points = less than half of all correct or
no response

 

1 point = correct answer, they will take
same time

0.5 points = incorrect answer with
partially correct reasoning or correct
answer with partially incorrectly
reasoned explanation

0 points = completely incorrect answer
and reasoning or no response

 

 

9,10

 

1 point = correct explanation and/or
diagram

0.66 points = correctly drawn diagram
and/or coherent, reasonable explanation
with some inaccuracies

0.33 points = incorrect but reasoned well
with supporting information

0 points = completely incorrect with no
explanation to back up, no response

 

Table 5: Scoring Rubric for Projectile Motion Tests

141

 

Momentum

 

Pretest Question #

Scoring Basis

 

1,2,3,4,5,6,7

Multiple choice:
1 point = correct
0 points = incorrect

 

1 point = correct directions on
snowballs before and after collision

0.5 points = correct either before or after
collision, but not both

0 points = before and after collision
incorrect or no response

 

1 point = correct explanation

0.5 points = partially correct explanation
- explanation had some holes in it or
reasoning gaps

0 points = incorrect answer or
reasoning, or no response

 

 

10

 

1 point = completely correct

0.5 points = partially correct explanation
— did not reference impulse-momentum
theory

0 points = incorrect answer or no
response

 

Table 6: Scoring Rubric for Conservation of Momentum Tests

142

 

Appendix E
Student End of Unit Survey: Projectile Motion

Please rate the following activities we did in class to the best of your ability. Any
additional comments would be very helpful!

5= This really helped me to understand the topic!

1= This activity completely confused me, and did not help me to better understand the
topic at all!

 

 

 

 

 

 

 

 

 

 

Projectile video during lecture I 2 3 4 5
Comments:
Projectile online simulation 1 2 3 4 5
Comments:
Demonstrations (Mr Potato Head, etc) 1 2 3 4 5
Comments:
Notes 1 2 3 4 5
Comments:

 

 

143

 

Projectile lab

Comments:

 

 

 

Problem sets

Comments:

 

 

144

Student End of Unit Survey: Graphing Motion

Please rate the following activities we did in class to the best of your ability. Any
additional comments would be very helpful!

5= This really helped me to understand the topic!

1= This activity completely confused me, and did not help me to better understand the
topic at all!

 

 

 

 

 

 

 

 

 

 

 

 

 

Moving man online simulation 1 2 3 4 5
Comments:
Motion sensor demonstration l 2 3 4 5
Comments:
Notes 1 2 3 4 5
Comments:
Lab 1 2 3 4 5
Comments:
Problems sets (worksheets) 1 2 3 4 5
Comments:

 

 

145

Student End of Unit Survey: Conservation of Momentum

Please rate the following activities we did in class to the best of your ability. Any
additional comments would be very helpful!

5= This really helped me to understand the topic!

l= This activity completely confused me, and did not help me to better understand the
topic at all!

 

 

 

 

 

 

 

 

 

 

 

 

Online simulation 1 2 3 4 5
Comments:
Demonstrations (rollerblades, potato, Newton’s cradle) l 2 3 4 5
Comments:
Notes 1 2 3 4 5
Comments:
Assignments/Bookwork l 2 3 4 5
Comments:
Lab 1 2 3 4 5
Comments:

 

 

146

Appendix F

Corresponding pre and post test question numbers linked to objectives

 

 

 

 

 

 

 

 

 

 

 

Graphing Motion
Pretest Posttest Objective covered

#1 #9 multiple choice D
#2 #10 multiple choice D
#3 #12 multiple choice B
#4 #13 multiple choice C
#5 #15 multiple choice B
#6 #4 problems A
#7 #5 problems A
#8 #3 b problems A
#9 #8 problems B

C

#10 #14 multiple choice

 

 

 

 

 

Table 7: Graphing Motion Pre/Post-Test Paired Questions

147

Projectile Motion

 

 

 

 

 

 

 

 

 

 

 

Pretest Posttest Objective covered
#1 #1 G
#2 #2 F
#3 #7a F
#4 #3 F
#5 #6c F
#6 #4 F
#7 #5a F
#8 #6a E
#9 #8 G

#1 0 #6b E

 

 

 

 

 

Table 8: Projectile Motion Pre/Post-Test Paired Questions

148

Momentum

 

 

 

 

 

 

 

 

 

 

 

Pretest Posttest Objective covered
#1 #1 0 J
#2 #2 K
#3 #3 J
#4 #8 J
#5 #6 J
#6 #5 K
# 7 #9 K
#8 #1 40 J
#9 #15 L
#1 0 #13c H and I

 

 

 

 

 

Table 9: Conservation of Momenttun Pre/Post-Test Paired Questions

149

Appendix G

Parental Consent and Student Assent Form
Collection of Data for Master’s Thesis

Dear Parents/Guardians and Students:

1 would like to take this opportunity to welcome you back to school and inform you about a
project that will be a part of Physics this semester. Over the past couple years I have been
working on a Master’s thesis through Michigan State University’s Department of Math and
Science Education (DSME). The culmination of this degree consists of a research project on
student learning, focusing on key areas where students typically struggle (projectile motion,
graphing motion, and conservation of momentum). The unit includes assignments, laboratory
experiments and activities, computer simulations, class demonstrations, and pre and post tests.
These items were designed to with the intent to improve student comprehension and retention of
the material covered in this course.

In order to evaluate the effectiveness of the study, normal class data will be collected from
students through pre and post tests, lab questions, surveys, and select questions from daily
assignments. With your permission I would like to use these data in my research thesis. The
names of students will be not be used in the thesis paper, as it will only include statistics and
anonymous samples of written work. Your privacy will be protected to the maximum extent
allowable by law. You and your child’s participation in this research study are completely
voluntary.

Your child will receive no penalty in regard to their grade should you deny permission for the use
of their data. Participation in this study will not increase or decrease the amount of work that is
required of your child. You may request that your child’s information not be included in this
study at any time and your request will be honored. To insure that I do not know who has and has
not volunteered to be in this study and perhaps unintentionally influence data, please return your
forms to the main office. Forms will be collected by office personnel and kept locked in that
location until after grades are turned in for the trimester. At that time I will access the forms and
use the data only from those whose permission I have received, omitting those who have not
consented.

If you are interested in having your child icipate in this study, please complete the attached

form and return it to me by September 11 , 2009. If you have any questions, please feel free to
contact me at Sf12bps@birmingham.k l 2.mi.us. Questions regarding the thesis project can also be
directed to Dr. Merle Heidemann at heidemgag2@msu.edu. If you have any questions or concerns
about your role and rights as a research participant, would like to obtain information or offer
input, or would like to register a complaint about this research study, you may contact,
anonymously if you wish, the Michigan State University Human Research Protection Program at
517-355-2180, FAX 517-432-4503, or e-mail irb@msu.edu, or regular mail at: 202 Olds Hall,
MSU, East Lansing, MI 48824.

Sincerely,

Sara Fetsco

Physics Teacher
Seaholm High School

This consent form was approved by the Social Science/Behavioral/Education Institutional Review Board
(SIRB) at Michigan State University. Approved 09/01/09 — valid through 08/31/10. This version supersedes
all previous versions. IRB# 09-687.

150

 

Please fill out the following consent information:
I voluntarily agree to have participate in
this study. (print student name)

Please check all that apply:

Data:

I give Ms Fetsco permission to use data generated from my child’s work in this
class for her thesis project. All data from my child shall remain confidential.

I do not wish to have my child’s work used in this thesis project. I acknowledge
that my child’s work will be graded in the same manner regardless of their participation.
Photography:

 

 

I give Ms Fetsco permission to use pictures of my child during her work on this
thesis project. My child will not be identified in these mediums.
I do not wish to have my child’s picture used at any time during this thesis project.

 

 

Signatures:

 

(Parent/Guardian Signature) (Date)
I voluntarily agree to participate in this thesis project.

 

(Student Signature) (Date)

***Important***
Return this form to the main office.

This consent form was approved by the Social Science/Behavioral/Education Institutional Review Board
(SIRB) at Michigan State University. Approved 09/01/09 — valid through 08/31/10. This version supersedes
all previous versions. IRB# 09-687.

151

BIBLIOGRAPHY

Akpan, J. 2001. “Which Comes First: Computer Simulation or Dissection or a Traditional
Laboratory Practical Method of Dissection.” Electronic Journal of Science
Education. 6 (4) July 8‘“, 2009

Beichner, RJ. 1996. “The Impact of Video Motion Analysis on Kinematics Graph
Interpretation Skills.” American Journal of Physics. 64 (10): 1272-1277

"Birmingham City, Oakland County, Michigan - DP-l . Profile of General Demographic
Characteristics: 2000." American F actF inder. Web. 09 July 2010.

Board of Education. “Demographic and lgnite Presentation 6.9.2009.” PowerPoint
presentation. Jun. 2009.

Brant, G., Hooper, E., & Sugrue, B. 1991. “Which comes first the Simulation or the
lecture?”

Choi, B & Gennaro, E 1987. “The Effectiveness of Using Computer Simulated
Experiments on Junior High Students’ Understanding of the Volume

Displacement Concept.” Journal of Research in Science Teaching. 24 (6): 539-
552

Deters, K. 2005. “An Inquiry Lab on Inclined Planes.” The Physics Teacher. 43 (3):
177-179

F inkelstein, N.D., Adams, W.K., Keller, C.J., Kohl, P.B., Perkins, P.B., Podolefsky, N.S.,
Reid, 8., LeMaster, R. 2005. “When learning about the real world is better done
virtually:

A study of substituting computer simulations for laboratory equipment. Physical
Review Special Topics: Physics Education Research. 1( (010103): 1-8.

Foti, S. & Ring, G. 2008. “Using a Simulation-Based Learning Environment to Enhance
Learning and Instruction in a Middle School Science Classroom.” Journal of
Computers in Mathematics and Science Teaching. 27 (1):103-120

Hofstein, A. & Lunetta, V.N. 1982. “The Role of the Laboratory in Science Teaching:
Neglected Aspects of Research.” Review of Educational Research. 52 (2): 201-
217

152

Hucke, L. & Fischer, H. 2002. “The Link of Theory and Practice in Traditional and in
Computer-Based University Laboratory Experiments.” In Teaching and Learning

the Science Laboratory. Ed. Psillos & Niedderer. Netherlands, Kluwer Academic
Publishers, 2002. 205-218

Hynd, C., McNish, M., Lay, K., Fowler, P. 1995. “High School Physics: The Role of
Text in Learning Counterintuitive Information.” Reading Research Report . 46: 1-
42 Journal of Educational Computing Research. 7 (4): 469-481

Lord, T. & Orkwisnewski, T. 2006. “Moving from Didactic to Inquiry-Based Instruction
in a Science Laboratory.” The American Biology Teacher. 68 (6): 342-345

Lunetta, V.N. & Hofstein, A. 1981. “Simulations in Science Education.” Science
Education. 65(3):243-253

Lynch, M.J. & Zenchak, J 2002. “Use of Scientific Inquiry to Explain Counterintuitive
Observations.” Proceedings of the Annual International Conference of the
Association for the Education of Teachers in Science. Charlotte, NC.

Michigan State University. Web. 08 July 2010.
<https://www.msu.edu/~brechtjo/physics/airTrack/airTrack.html>.

Milne, C. & Oteino, T. 2007. “Understanding Engagement: Science Demonstrations and
Emotional Energy.” Science Education. 91 (4): 523-553

PhE T: Free Online Physics, Chemistry, Biology, Earth Science and Math Simulations.
Web. 09 July 2010.

Roth, W., McRobbie, C. Lucas, K. & Boutonne, S. 1997. ”Why Students Fail to Learn
from Demonstrations.” Journal of Research in Science in Science Teaching. 34
(5): 509-533.

Roth, W., Lucas, K. 1997. “From “Truth” to “Inverted Reality”: A Discourse Analysis of
High School Physics Students’ Talk about Scientific Knowledge.” Journal of
Research in Science Teaching. 34 (2): 145-179.

Royuk, B. & Brooks, D. 2003. “Cookbook Procedures in MBL Physics Exercises.”
Journal of Science Education and Technology. 23 (3): 317-324

Shepardson, D., Moje, E., & Kennard-McClelland, A. 1994. “The Impact of a Science
Demonstration on Children’s Understandings of Air Pressure.” Journal of
Research in Science Teaching. 31 (3): 243-258.

Vision Internet. "Birmingham, MI : Stats and Facts." Birmingham, MI .' Homepage. Web.
09 July 2010.

153

A

“11111111111111fillflllfllljjlllillllfl