a 107 lb little red wagon full of kids is on the top of a 41.4 m hill. the wagon falls down the hill and up a 14.5 m hill. how fast is it going on the top of the second hill if there is no friction?

Answer 1

It falls 41.4 -14.5 meters
so it loses m g h = m g (41.4-14.5) jouless of potential energy
that becomes kinetic energy
so
(1/2) m v^2 = m g (41.4-14.5)
so
v = sqrt [ 2 * 9.81 *(41.4-14.5) ]

Answer 2

@Damon. Question where did the mass go?