Mousetrap Car
A snapping mousetrap's spring becomes a drivetrain that powers a car several metres in one shot.
Start building ↓The build
Mount the trap
Fix the mousetrap to a lightweight chassis.
Add wheels
Build axles and large rear wheels for distance.
Tie the string
Attach string from the trap arm to wind around the axle.
Set & release
Set the trap to wind the string, then let it snap to drive forward.
The wound spring stores elastic energy; as the arm snaps shut it pulls the string, unwinding it from the axle to spin the wheels.
A closer look
A longer lever arm and bigger wheels trade torque for distance; reducing friction lets more spring energy become travel.
Variables to test
- 1 Lengthen the trap's lever arm — farther or slower?
- 2 Compare large vs small drive wheels for distance.
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