This document describes how a pullback toy car works. When pulled back, the spring inside winds up and coils tighter around the wheel shaft. When fully wound, the car is ready to go and letting go causes the spring to unwind fast, propelling the car forward.

1. Powered toy
Pullback car

2. The car is still because
there is no force moving it.

3. When the car is pulled back the
spring inside winds up
PULL back

4. The spring coils tighter and tighter
around the wheel shaft

5. HOLD. HOLD!
Don’t let go yet!
The car can’t be pulled back
anymore and is ready

6. The spring unwinds FAST and
makes the car go forward