A rock of a mass 0.2kg is attatched to a 0.75m long string and swung in a vertical plane. What is the slowest speed that the rock can travel and still maintain a circular path.

so, i started with the following equation: Fc= mv2/r
but where do i go from there to solve for v (what can i change Fc to? )

4 answers

http://www.jiskha.com/display.cgi?id=1256408250
so are you suggesting that there is no tension when the rock is at the top of the circle?
no tension at the absolute minimum velocity.
okay, thanks !