Catapult: Energy and Projectile Motion Project
Date Assigned: Februarys 26th
Mandatory Test Launch: March 6th
Date Due: Beginning class March 20th
Purpose: To augment knowledge of energy, energy storage mechanisms, and projectile motion
Objective: To construct a catapult utilizing elastic energy in order to hit a target
Specifications:
 Your launcher may not exceed 0.5 x 0.5 x 0.5m (it may not include you as a part)
 You may work individually or in a group not exceeding two members
 You may not use a prebuilt catapult, or a catapult kit
Lab Safety:
 Use extreme caution; rattraps and catapults have the ability to break your fingers and/or blind
you
 In the event that you use power tools, do so only under parental supervision and wear safety
goggles
 Never launch/aim a projectile at anyone or anything other than open space
 Be aware that your projectile may misfire; take all safety precautions to protect your eyes and
fingers (not to mention the rest of you)
Target:
 Will rest flat
 Will rest 2 meters away from the origin line (the catapult may rest just behind the origin line, or
up to half a meter behind the origin line)
 See the sample target for dimensions and point allotments
 Carbon paper will be used to show the initial strike of the ball
Requirements:
 One Catapult per group
 One ball per group: golf ball or marble
 Concluding questions typed and stapled to the back of this packet.
Day of Practice Launch:
 Catapult should be all constructed, finished and ready to go at the start of class.
 You will measure out 2 m and set up your catapult and target.
 Shoot your projectile, look at results, and make alterations.
 Make sure your teacher sees at least one of your practice shots.
Day of the Launch:
 You may not alter or work on your model once the first group has started (only exception-see
practice launch)
 You will watch and be interested in everyone’s launch.

Your group will have two practice launches before the grading starts.
o The practice launches may be declined
o You will only have one minute from the first launch of your practice until your graded
launch must begin.
o You may make adjustments to your model during the test launch as long as it is during the
one minute allotment

Graded launch
o You will have three consecutive launches
o No alterations may be made to your launcher during the graded portion (if it breaks, it
breaks)
o Your goal is to be accurate
o Delay of launch will result in deduction of points
Questions: Be specific, thorough and analytical when answering! Type your answers and attach them to
the back of this packet!
1. Sketch and label a diagram of your catapult. Make sure to include dimensions in your sketch.
2. What modifications did you make to your original catapult design? Give a rational as to why you
made these changes and what affect these changes had.
3. Explain the energy storage mechanisms of your catapult.
Grade:
Possible Points
Catapult is ready at beginning of class on the test
launch day and actual launch day
15
Specifications are met
25
Theme
5
Safety
10
Three Shots
30
Concluding questions
15
Points awarded