Work Done by the Resistive Force
What is the scenario in this question?
A bicyclist rides 1.59 km due east, while the resistive force from the air has a magnitude of 7.00 N and points due west. The rider then turns around and rides 1.59 km due west, back to her starting point. The resistive force from the air on the return trip has a magnitude of 7.00 N and points due east. Find the work done by the resistive force during the round trip.
Answer:
The required work done by the resistive force = -22.3 kJ
The given scenario describes a bicyclist riding back and forth with resistive forces from the air acting against her. In this case, we are asked to find the work done by the resistive force during the round trip. The work done by a force is calculated as the product of the force and the displacement.
When the bicyclist travels east, the resistive force points west. Upon returning west, the resistive force points east, indicating opposite directions. The angle between these displacements is 180 degrees apart.
We can calculate the work done by the resistive force as follows:
W = -2 × 7.00 × 1590
W = -22260 J
Therefore, the work done by the resistive force is -22.3 kJ.