PROJECTILE MOTION CATAPULT PROJECT
PHYSICS 621
OBJECTIVES:
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To apply the laws of Physics and the equations of projectile motion to design a catapult that can
accurately launch a racquet ball and hit a designated target.
To compare experimental data to theoretical data and understand differences between the two.
CRITERIA:
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In this project you will be building racquet ball catapults. Your catapult will need to be able to
launch a racquet ball in the range of 5-20 m. (Every catapults range will be different but it should
be able to shoot somewhere within this distance)
Your catapult must be able to launch a racquet ball at any angle between 0 and 90 degrees.
On testing day you will be given the distance to the target and you will then have 2 minutes to
make adjustments to your catapult. Therefore, you must design and test your catapult so that
on testing day you can make whatever adjustments are needed.
All catapults should be composed of scrap materials found that you provide or that can be
readily found in the physics lab (possibly the Industrial Arts lab???). You may use materials from
home, but try to make your catapult out of materials you already own. This project should not
cost you anything personally.
If you decide to work on this project at home (I strongly advise against this. Time will be given in
class for assembly), be sure to have a parent or guardian present. Any cutting of wood or other
materials must be done at school under supervision.
The appearance of the catapult will not be judged, but you should pay careful attention to
design elements that affect the ability of your catapult to adjust to new distances.
You will be working in groups of one/two/three and you need to turn in only one report per
group. However, you will be completing a peer evaluation for every member in your group, so
be sure that each team member is contributing in a meaningful way.
You will have three to four periods to design and build the catapult (keep this in mind so that
you can work at home if necessary).
FORMAL REPORT:
You will be graded on the following items:
1.) Design Plan
2.) Data Analysis
3.) Organization and Presentation of Report
4.) Conclusion
*** PLEASE SEE THE RUBRIC FOR ADDITIONAL DETAILS ***
1.) YOUR DESIGN PLAN MUST INCLUDE:
a.) A list of materials used (should be bulleted)
b.) A diagram of your catapult (preferably done on a computer drawing program). The diagram
should have all dimensions labeled (including units) and should be neatly presented. Your
diagram should be drawn or printed on plain white paper and should fill most of a single
page.
2.) YOUR DATA ANAYLSIS MUST INCLUDE:
a.) Data table that includes time of flight (s), distance flown in horizontal direction, and the
angle of launch. Complete calculations for one sample trial should be included in this
section. (Please type)
b.) A value for the average initial velocity of the marshmallow and an explanation of how initial
velocity of the marshmallow was determined.
c.) How did changing the angle affect the characteristics of you trajectory? The initial velocity?
(Can be answered in the “Conclusion” section of your report)
3.) ORGANIZATION AND PRESENTATION:
a.) The report should be neatly typed and sections should be well marked with titles.
b.) The report should be proofread for any spelling mistakes.
c.) All calculation shown in the report should be done using the problem solving strategy
explained in class.
d.) All answers are presented in complete sentences excluding the list of materials which should
be bulleted.
4.) CONCLUSION:
Your conclusion should include an overview of your findings and describe any sources of
error that might be present. Possible design alterations for future versions could be
included here as well. The answers to any questions asked during the project should be
answered in this section.
Physics 621 Catapult Project Peer Evaluation Rubric
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4
Group member
participated fully and
was always on task in
class.
3
Group member
participated most
of the time and
was on task most
of the time.
2
Group member
participated but
wasted time
regularly or was
rarely on task.
1
Group member did
not participate,
wasted time, or
worked on
unrelated material.
Group member
assumed leadership in
an appropriate way
when necessary by
helping the group
stay on track,
encouraging group
participation, posing
solutions to problems,
and having a positive
attitude.
Group member
listened carefully to
others’ ideas.
Group member
sometimes
assumed
leadership in an
appropriate way.
Group member
usually allowed
others to assume
leadership or often
dominated the
group.
Group member did
not assume
leadership or
assumed it in a
nonproductive
manner.
Group member
usually listened to
others’ ideas.
Feedback
Group member
offered detailed,
constructive feedback
when appropriate.
Group member
offered
constructive
feedback when
appropriate.
Group member did
not listen to others
and often
interrupted them.
Group member did
not offer
constructive or
useful feedback.
Cooperation
Group member
treated others
respectfully and
shared the workload
fairly.
Group member
usually treated
others respectfully
and shared the
workload fairly.
Time
Management
Group member
completed assigned
tasks on time.
Group member
usually completed
assigned tasks on
time and did not
hold up progress
on the projects
because of
incomplete work.
Group member
sometimes did not
listen to others’
ideas.
Group member
occasionally
offered
constructive
feedback, but
sometimes the
comments were
inappropriate or
not useful.
Group member
sometimes treated
others
disrespectfully or
did not share the
workload fairly.
Group member
often did not
complete assigned
tasks on time, and
held up completion
of project work.
Participation
Leadership
Listening
Group member
often treated others
disrespectfully or
did not share the
workload fairly.
Group member did
not complete most
of the assigned
tasks on time and
often forced the
group to make lastminute
adjustments and
changes to
accommodate
missing work.
PHYSICS 621
Catapult Project Rubric & Grading Sheet
Deductions
Score
Catapult (30 points)
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Ready to go on time (4)
Sized appropriate (2)
Quality of Construction (10)
Trigger (5)
Originality (9)
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Design Log Book (15 points)
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Detailed progress of project (7)
Sketches of catapult (3)
Rough calculations (5)
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Design Report (39 Points)
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Team names (.5)
Neatness (1)
Materials List (1)
Visual Plans (8)
Design Procedure (8)
Data Analysis (12)
Conclusion (8.5)
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Launch Capabilities (8 Points)
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Fired safely (1)
Range 2 m (7)
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Accuracy (8 Points)
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Hit target “on the fly” within 2 tries
(8)
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Total Score
/ 100