Numerical Example – Multiple Pulleys

In reference to the diagram, the pulley is connected to a 100 lb weight. What is the mechanical advantage of this pulley arrangement and how much force do we need to apply to pull this weight?

Solution

a. Since two ropes are applying the input force on the weight, the mechanical advantage of this arrangement is 2.

b. Since the mechanical advantage of this arrangement is 2, therefore, we will need to apply 50 lb force to lift a 100 lb weight.