Question

The work output of a lever used to lift books is 30 Joules and the work input is 60 Joules.

What is the efficiency of this lever?

Answer 1

50%

Step-by-step explanation:

Given parameters:

Work output = 30J

Work input = 60J

Unknown:

Efficiency of the lever = ?

Solution:

To solve this problem, the efficiency is taken as the ratio of the work output to that of the work input;

Efficiency = Work output / Work input x 100

Efficiency =
`(30)/(60)` x 100 = 50%