Question

A bicyclist rides 5.0 km due east, while the resistive forcefrom the air has a magnitude of 3.0 N and points due west. Therider then turns around and rides 5.0 km due west, back to herstarting point. The resistive force from the air on the return triphas a magnitude of 3.0 N and points due east.
a) Find the work done by the resistive force during the roundtrip.
Based on answer in part A.
b) Is the resistive force a conservative force? explain.

Answer 1

Answer:

a) Find the work done by the resistive force during the roundtrip.

W=-30kJ

b) Is the resistive force a conservative force? explain.

The resistive force is not a conservative force since the work done during the round trip is not zero

Explanation:

The worf done on object y a constant force F is given by:

W= (F  cos ∅)S

Where S is the displacement and ∅ is the angle between the force and the displacement.

The displacement of the bicycle during each part of the trip is s=5000m and teh magnitude of teh resistance force is F=3.0N

∅1=180° he angle between the displacement and the force

W1=W2

W1 = (3.0 cos180) 5000m

W1=-15.O kJ

W=W1+W2

W=-30kJ

The resistive force is not a conservative force since the work done during the round trip is not zero