Question

A pulley system comprises of two pulleys, one fixed and other movable.

1. Draw a labelled diagram of the arrangement and show clearly all the forces acting on it.
2. What change can be made in movable pulley of this system to increase the mechanical advantage of system?

Answer 1

(a)

(b) To increase the mechanical advantage of this system, the following two changes should be made to the movable pulley:

1. Reduce its weight: The frame and the disc of the movable pulley should be made as lightweight as possible. If the pulley is heavy, a significant amount of effort is wasted just to lift the pulley itself, which decreases the MA.
2. Reduce friction: The axle and bearings of the movable pulley should be well-lubricated (using oil or grease) to minimize frictional resistance against the moving string.