A 30 kg child slides down a playground slide at a constant speed. The slide has a height of 3.8m and is 7.8m long. using energy considerations, find the magnitude of the kinetic friction force acting on the child.

2 answers

Since the KE does not change, the work done by gravity equals that done by friction. Thus the friction force times the distance slid equals the change in potential energy m g h

m g h = F * 7.8
2293.2