ill try this again w/o the link.... my project is to make a wooden car move 7 m usuing only the energy from a mouse trap when it is set off. and i cant make any modifications to the mouse trap....ive tried one but its not workin correctly and i think ive had to of seen every website but i cant figure out how to do it...so if u could please help me...thank you!

Part of the sport of mouse trap cars is to figure out/engineer things on your own.
So only a few hints.
The spring in your mouse trap is the engine.
Your problem needs to translate the energy into rotary motion of the wheels..
String a cam..
The constraint of not modifying the mouse trap..
Can you tie a string to it? etc.
let us know how you did and what the record was in the class.
..slow and steady often wins the race..

Peteeo's right, but you deserve another small hint. The mousetrap releases its energy FAST. You need to convert that energy to something that releases more slowly. Thought about a rubber band?