A bicyclist travels on the hill shown in Figure P6.74. She begins from rest at the top of...

A bicyclist travels on the hill shown in Figure P6.74. She begins from rest at the top of the hill, coasts all the way to the bottom, and finds that she gets to a point approximately 60% of the way up the other side before the bicycle comes (instantaneously) to rest. The total mass of the bicyclist plus the bicycle is 100 kg. (a) Estimate the total work done on the bicycle by all frictional forces (including air drag), (b) Assuming the main frictional force is due to air drag, find the approximate magnitude of this force throughout the motion. Hint: Calculate the power due to air drag by assuming her speed during the entire time is a constant and approximately equal to vave.

Figure P6.74