A roller coaster is pulled up a hill of height 95m before being released to coast down a ramp that is inclined at 56 degrees above the horizontal. Assume that the car is at rest just before it starts down the ramp.
(a) Assume that energy is conserved (i.e. ignore friction and air resistance) and find the car's speed at the bottom of the ramp.
(b) In the real world, friction does act on the car as it coasts down the ramp, and its speed at the bottom is only 41.2 m/s. If the mass of the car is 228kg, how much work is done on the car by frictional forces during its trip down the ramp?
(c) What is the magnitude of average frictional force on the car?