Question

A machine has an efficiency of 80%. How much work must be done on the machine so to make it do 50,000 J of output work?

Answer 1

Work formula is Work=N∙M or Joule (J)

So you have the following given:

50 000 is the output work

.8 is the efficiency

 if you input the given = 50000 = .8*J

To get the answer just divide 50000 by .8 to get the answer.

62,500 J is the amount of work to be done.

Answer 2

Answer;

62,500 Joules

Explanation;

• Efficiency is a measure of how much work or energy is conserved in a process. It can be stated as the percentage of the output work divided by the input work minus the work lost from to friction and heat.

Efficiency = (output work/ input work) × 100%

        80 % = 50,000 / input work  × 100%

             0.8 = 50,000 /input work

Input work = 50,000/0.8

                  = 62500 Joules

Thus; the work input is 62,500 joules.