Grand Prix Racers

Purpose: To build a vehicle that can be propelled using the mechanical energy stored inside an inflated balloon, rubber band, mousetrap etc. and measure and calculate various kinematic quantities.

Learning Indicators:

J4. Design and construct a device to perform a specific function, then redesign for improvement (e.g., performance).

Procedure/Specifications

• You may use only mechanical forms of stored energy to propel your car (i.e. no electrical or fuel-powered motors, no CO₂ canisters, etc.). If in doubt about whether your propulsion method is acceptable – ask!
• Your stored energy must be part of your vehicle – in other words not external sling shots, etc.
• Two photogates will be set up 0.5 m apart.
• The photogates can be at any height (up to the top of a ring stand).
• Your car will be released from rest at the first photogate and the time will be measure to the second photogate.
• Something on your car must pass through the photogates to trigger them.
• You car must be able to go straight for the first 0.5 m.
• Your total displacement will be measured (in a straight line using a metric measuring tape) from where the car starts to where it stops.
• Your total time will be measured with a stop watch from when the car starts to when it stops.
• You will be allowed class time to test your cars and then more time to take them home and improve them for race day.

You will need to measure and calculate:

During the first 0.50 m

· time – will be measured with photogates

· average velocity

· initial velocity

· final velocity

· acceleration

For the whole trip:

· time – will be measured with a stopwatch

· displacement

· average velocity

Points will be awarded for:

• improvements, modifications, creativity and effort (30 points)
• correct calculations (30 points)
• fastest “pick-up” (largest acceleration) for the first 0.5 m (10 points)
• fastest average velocity for the whole trip (10 points)
• longest displacement for the whole trip (10 points)

References:

• Hyperphysics: Motion:

http://hyperphysics.phy-astr.gsu.edu/hbase/mot.html

• Physicsclassroom.com: 1-D Kinematics
• Lesson 1 - http://physicsclassroom.com/Class/1DKin/U1L1a.html
• Lesson 6 - http://physicsclassroom.com/Class/1DKin/U1L6a.html

Grand Prix Racers – lab sheet

Name: ______________________________ Period: ___________________

THIS SHEET MUST BE TURNED IN BEFORE YOU LEAVE ON RACE DAY.

Practice day:

Through the photogate:

Data: Calculations (show work and equation used in space below):

displacement (Dx) = 0.50 m average velocity (v_ave) = _____ m/s

initial velocity (v_i) = 0.0 m/s final velocity(v_ave) = _____ m/s

time (t) = _____ s acceleration (a) = _____ m/s²

Complete trip:

Data: Calculations (show work and equation used in space below):

displacement (Dx) = _____ m average velocity (v_ave) = _____ m/s

time (t) = _____ s

Race day:

Through the photogate:

Data: Calculations (show work and equation used in space below):

displacement (Dx) = 0.50 m average velocity (v_ave) = _____ m/s

initial velocity (v_i) = 0.0 m/s final velocity(v_ave) = _____ m/s

time (t) = _____ s acceleration (a) = _____ m/s²

Complete trip:

Data: Calculations (show work and equation used in space below):

displacement (Dx) = _____ m average velocity (v_ave) = _____ m/s

time (t) = _____ s

Before you come race day, do/answer the following. Attach another sheet of paper if you wish.

1. Provide a detailed drawing of your design labeled with important features.

2. Describe your design. (what materials did you use, why did you decide to build it this way, how do certain features help meet the objectives, etc.)

3. What modifications did you make to your original?