A O.100-kg potato is tied to a string with length 2.50 m, and the other end of

Question:

A O.100-kg potato is tied to a string with length 2.50 m, and the other end of the string is tied to a rigid support. The potato is held straight out horizontally from the point of support, with the string palled taut, and is then released.
(a) What is the speed of the potato at the lowest point of its motion?
(b) What is the tension in the string at this point?