Physics Angular Momentum Problem?

Question

Soooo, heres the question I'm trying to work on.

A small 0.500kg object moves on a frictionless horizontal table in a circular path of radius 1.00m. The angular speed is 6.28 rad/s. The object is attached to a string of negligible mass that passes through a small hole in the table at the center of the circle. Someone under the table begins to pull the string downward to make the circle smaller. If the string will tolerate a tension of no more than 105 N, what is the radius of the smallest possible circle on which the object can move?

Help? Thanks in advance!

Answer 1

By conservation of angular momentumm, mw1 r1 = m w2 r2. And you have m w^2 r2 = 105 N. You know m, w1, and r1, so you can solve for r2.