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3 years ago

15

the useful power out of an electric motor is 20w and the total power into the motor is 80w calculate the percentage efficiency o

f the motor

1 answer:

olganol [36]3 years ago

4 0

Answer:

25%

Explanation:

Efficiency is the ratio of power out to power in.

e = 20 W / 80 W

e = 0.25

The motor is 25% efficient.

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