Science Buddies: "Ask an Expert"

So basically i made my sub already, I just cant figure out how to set off the mouse trap and have somthing rise to the top again. My experiment is A submarine that has to float for three second, then sink, then have somthing come off the orginal sib and float again. All i have right now is a containter with hole and coins as wieght in it and a mouse trap secured on top. PLEASE HELP. I cant figure out what to put on the mouse trap that will set it off when it hits the bottom then rise again. My orginal thought was to attach a upside down cup to the trap so when it goes off it will float to the top. The only problem with that is i cant figure out how to attach it and how to set off the trap. Any Ideas?

I'm sorry, I can't quite figure out how your project is supposed to work. Is this a project you found either on this or some other website that I could look up?

There are a lot of ways I could imagine a mouse trap being used for this... for example, it could pull a cork out of a container with ballast (heavy stuff in it), that would then fall out through the hole, increasing the buoyancy of the submarine.

If the only question is how to set off the mouse trap, that would depend on how it's mounted... but anything you attached to the trigger that extends below the bottom should work. Be careful setting mouse traps, as they can break fingers.