Question

Jonathan is riding a bicycle and encounters a hill of height 8.30 m. At the base of the hill, he is traveling at 7.00 m/s. When he reaches the top of the hill, he is traveling at 0.60 m/s. Jonathan and his bicycle together have a mass of 90.0 kg. Ignore friction in the bicycle mechanism and between the bicycle tires and the road.

What is the total external work done on the system of Jonathan and the bicycle between the time he starts up the hill and the time he reaches the top?

Answer 1

The total external work done on the system of Jonathan and the bicycle can be calculated using the work-energy principle.

Step-by-step explanation:

The total external work done on the system of Jonathan and the bicycle can be calculated using the work-energy principle. The work done on an object is equal to the change in its kinetic energy. First, we need to calculate the initial and final kinetic energy of the system.

1. Initial kinetic energy: KEi = 0.5 * mass * (initial velocity)2
2. Final kinetic energy: KEf = 0.5 * mass * (final velocity)2

Then, we can calculate the work done:

Work done = KEf - KEi

Plugging in the given values, we get:

Initial kinetic energy (KEi) = 0.5 * 90.0 kg * (7.00 m/s)2

Final kinetic energy (KEf) = 0.5 * 90.0 kg * (0.60 m/s)2

Work done = KEf - KEi