posted by Anonymous .
A 57-kg lead ball is dropped from the leaning tower of Pisa. The tower is 56 m high.
(b) What is the speed of the ball after it has traveled 2.5 m downward?
change in potential energy = (1/2) m v^2 = m g (2.5)
v^2 = 2 (9.8)(2.5)
v = 7 m/s
mass does not matter