Question

Tori experiments with pulleys in physics class. She applies 70 newtons of force to a single pulley to lift a bowling ball. By adding another pulley, she’d get a mechanical advantage of 2. What’s the minimum input force she’ll need to lift the ball if she adds another pulley?

Answer 1

Answer: 35 N

Hope this helps! :D <3

-Maggie

Answer 2

The minimum input force she'll need to lift the ball is 35 N.

Explanation:

Mechanical advantage of a single pulley is 1. As, she applies 70 N of force to lift the bowling ball, so the output force(weight of the ball) is also 70 N.

Now, adding another pulley gives a mechanical advantage of 2. We have,

M.A = (Output Force)/(Input Force)

Substituting the values we get,

$2=\frac{70}{F_{i}}$

$F_{i}=\frac{70}{2}$ = 35 N

Input force equals to 35 N needs to be applied.