Question

"A small 0.5 kg object moves on a frictionless horizontal table in a circular path of radius 1 meter. 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 mop more than 105 N, what is the radius of the smallest possible circle on which the object can move?"

I already know the answer is 0.573 meters. I just need someone to help me figure out how to set up the problem.