Question

You have designed a machine that requires 1000 J of work from a motor for every 800 J of useful work done by the machine. What is the efficiency of the machine?

Answer 1

Answer:

80%

Explanation:

$efficiency = \frac{useful \: work \: done}{total \: energy \: input}$

800 / 1000 = 0.8

Efficiency = 0.8 *100 = 80%