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?
100( power out ) /power in
100*3760/4000 = 94 %
To determine the efficiency of the machine, we need to use the formula:
Efficiency = (Useful work output / Energy input) * 100%
In this case, the energy input is given as 4,000 W and the useful work output is given as 3,760 W.
Plugging these values into the formula, we get:
Efficiency = (3,760 W / 4,000 W) * 100%
Efficiency = 0.94 * 100%
Efficiency = 94%
Therefore, the efficiency of the machine is 94%.