Question

A company is interested in buying a new machine to replace their outdated equipment. However, before committing to the purchase, the company asks the manufacturer to provide data on a certain machine's efficiency. The data suggests that with a supplied energy at a rate of 1,600 W, the machine will do useful work at a rate of 1,540 W. What's the efficiency of this particular machine?

A. 84.21%
  B. 96.25%
  C. 103.90%
  D. 77.00%

Answer 1

I know that the answer is B.

Answer 2

Efficiency is defined as the measure of the amount of work or energy is conserved in a certain process. At all times, in every process, work or energy is always lost or wasted due to certain interference. Not all work given is converted to useful work or energy. Thus , efficiency is calculated by dividing the energy or work output to the energy or work input then the value is multiplied by 100 to express efficiency as percentage.

Efficiency = work output / work input Efficiency = (1540 J / 1600 J) x 100= 96.25%
Thus, the answer is B.