Efficiency Calculation of a Machine

What is the efficiency of a machine that is supplied energy at a rate of 4,000 W and does useful work at a rate of 3,760 W?

Choose the correct answer:

Answer: 94 percent

When calculating the efficiency of a machine, you divide the amount of useful work by the amount of energy supplied. In this case, the machine is supplied energy at a rate of 4,000 W and does useful work at a rate of 3,760 W.

Therefore, the efficiency can be calculated as follows:

Efficiency = (Useful work / Energy supplied) x 100%

Efficiency = (3,760 / 4,000) x 100%

Efficiency = 0.94 x 100%

Efficiency = 94%

So, the efficiency of the machine is 94 percent.