## Rotation, friction and size (mass/radius?)

Basically, I am looking to create a simple physics game in flash for my game design course called "spin the banana" where the player sets the force which is then applied to the banana (imagining the banana is just a disk-shaped object to keep it simple) taking into account the friction and the size of the banana (radius of the disk?).

I'm competent with numbers when given an equation to work with so I just need an equation or set of equations to help me work out the rotation of a spinning object using the friction, size of object and force (and anything else I may need to add in to complete the equations).

Thanks for any help.
 Mentor Friction between what and what? Force between what and what, applied where and how long? If your banana slides on some solid surface (similar to curling), friction can be calculated with the mass, g and a dimensionless constant of the friction. For the momentum, just multiply that stuff, for torque, it might need an integration over the surface of the disk (which has to be done once, afterwards you get some parameter which you can use).