Centripetal Force?

Question

A space station is in the shape of a hollow ring with an outer diameter of 150 m. How fast should it rotate to simulate Earth's gravity--that is, so that the force exerted on an object by the outside wall is equal to the object's weight on Earth's surface?

Answer 1

Centripetal Force = mv^2/r.
Newton's 2nd says that F = m*a, so
mv^2/r = m*a and a = v^2/r.

If you want a to be 9.8m/s^2, substitute that in for a and solve for v.