Rubber-Band Car
Wind up a rubber band and store energy that launches a lightweight car across the floor.
Start building ↓The build
Build the chassis
Make a light frame and add axles with wheels.
Attach the band
Anchor one end of the rubber band to the body, the other to the rear axle.
Wind it up
Roll the car backwards to wind the band around the axle.
Release
Let go — the band unwinds and drives the wheels.
Winding stretches the rubber band, storing elastic potential energy that converts to rotational kinetic energy in the axle as it unwinds.
A closer look
Energy stored equals the work done winding; lighter cars and less friction turn more of it into distance travelled.
Variables to test
- 1 Add winds and measure distance — is it linear?
- 2 Change wheel size. Bigger wheels: farther or slower?
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