Mouse Trap Cars

A mousetrap powered car is a vehicle that uses a mouse trap for a motor and a string to transmit force. In this method one end of a string is attached or tied to the arm on the mousetrap and the other end of the string is wound around an axle.
By winding the string around the axle the mouse trap's spring is stretched and now you have your stored energy. As the mousetrap car is released the mouse trap pulls the string off of the axle causing the wheels to turn and off the vehicle goes.

There are many different designs for mouse trap cars. Some are made for distance and others made for speed. 

Video: Mouse trap car for distance

Video: Mouse trap car for speed

There are many different designs online. Most use either cd's or records as wheels. Many also use levers to reduce the amount of torque applied to the wheels. Overall the different designs of the cars show all the different ways the cars can be made and still work effectively. Some designs on websites also have kits you can buy to make the car easier.