1. The problem statement, all variables and given/known data If you twirl a ball attached to a cord in a vertical circle, there would be a critical speed at the top for which the tension in the cord is zero. This is because the force of gravity supplies all the centripetal force necessary to complete the circle. How slowly would you twirl an 800-g ball so that it would describe a vertical circle of radius 1 m? 2. Relevant equations Because we are looking for the slowest speed that the ball can have in order to complete the circle Fg=Fc And therefore, through rearranging equations found that v=√gR 3. The attempt at a solution So from that manipulated equation found that v=3.13m/s If anyone could just verify my answer, that would be greatly appreciated! Thank you so much for your help and time!