A sled and rider, gliding over horizontal, frictionless ice at 5.0 m/s, have a combined mass of 86 kg. The sled then slides over a rough spot in the ice, slowing down to 3.5 m/s.
a) What is the coefficient of friction between the sled and the rough spot?
b) How much work is done by friction in slowing the sled down?
c) What is the acceleration of the sled?
d) What is the net force acting on the sled?
