Equations - Circular Motion

Velocity = radius * angular velocity (the latter in radians per second)

Centripetal acceleration = radius * angular velocity²

Escape velocity = Sqr Root (2 * g * radius of planet) (where g is the gravitational constant for that planet)

Period of Simple Harmonic Motion = 2 * Pi / angular velocity or more usefully, for a pendulum: Period = 2 * Pi * Sqr Root (length/g)

http://en.wikipedia.org/wiki/Circular_motion