Ball hanging from string (centripetal forces) #1

Question

A ball, attached to a string, moves in a circle. How does the tension of the string change if the speed of the ball is doubled?

Answer 1

If the tension is the only centripetal force present, and you double the speed without changing anything else, the tension is quadrupled.

 

T = mv²/r

 

T' = m(2v)²/r = 4mv²/r = 4T