A bicyclist can coast down a 5° hill at a constant 6.0 km/h. Assume the force of friction (air resistance) is proportional to the speed v so that Ffr = cv.
(a) Calculate the value of the constant c.
(b) What is the average force that must be applied in order to descend the hill at 20 km/h? The mass of the cyclist plus bicycle is 77 kg.
13 answers