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PRACTICE / Power

The electricity bill includes losses

A motor supplies 600 W of useful mechanical output with efficiency 75%.

Find its input power.

Organize the givens & assumptions
  • Pout = 600 W
  • η = 0.75

Steady operation; efficiency is useful output power divided by total supplied power.

  1. A800 W800\ \mathrm W
  2. B450 W450\ \mathrm W
  3. C600 W600\ \mathrm W
  4. D200 W200\ \mathrm W

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