# [Help] Grade 12 University Prep Physics Design Project

1. The Project
I must build a boat that is able to propel itself via elastic or gravitational energy 1.0 metres. After it has moved 1.0m, it must automatically shoot a projectile 2.0m perpendicular to the movement.

2. Rules
The boat cannot touch the bottom of the 10 cm deep pool.
Any solid projectile may be used.
I have about a week as of June 6th, 2011.

## The Attempt at a Solution

I am thinking about a propeller to move the boat, and a mousetrap to fire the projectile. However, the two systems must be interconnected, obviously. That's the hard part, and I don't know whether a propeller would be the most efficient way of doing it.

Help would be appreciated!

Related Introductory Physics Homework Help News on Phys.org
Consider that a string could be used as a timing mechanism; as the propeller spins, the string gets pulled tighter (as it wraps around the axle.)

Another idea is a very well lubricated nut timing mechanism. Place a nut on the (threaded) axle, and don't allow it (the nut) to rotate. As the axle rotates, the nut will move along the axle.

You might also be able to use a string fastened to the shoreline as your timing mechanism.

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I am now using a string as a mechanism. I am wrapping string around a rod with a propeller. As the propeller spins, it pulls on a piece of wood which triggers a mousetrap, which fires a projectile.