Solution Found!
Solved: The 4-lb pulley has a diameter of 1 ft and the
Chapter 8, Problem 8-120(choose chapter or problem)
The 4-lb pulley has a diameter of 1 ft and the axle has a diameter of 1 in. If the coefficient of kinetic friction between the axle and the pulley is \(\mu_{\mathrm{k}}\) = 0.20, determine the vertical force P on the rope required to lift the 20-lb block at constant velocity
Questions & Answers
QUESTION:
The 4-lb pulley has a diameter of 1 ft and the axle has a diameter of 1 in. If the coefficient of kinetic friction between the axle and the pulley is \(\mu_{\mathrm{k}}\) = 0.20, determine the vertical force P on the rope required to lift the 20-lb block at constant velocity
ANSWER:
Step 1 of 5
First, we'll draw the free-body diagram of the shaft.
Note that the pulley rotates counterclockwise, so the shaft rotates clockwise relative to the pulley. Therefore the friction force must rotate counterclockwise in order to prevent the rotation.