Question

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

Answer 1

Efficiency = (output power) / (input power)

                = (3,760 joule/sec) / (4,000 joule/sec)
 
               =    3,760 / 4,000  =  0.94  =  94%
 

Answer 2

your answer is 94 percent

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