MotorsQuestion 1487 of 1506

A motor takes 40 kW from the supply and delivers 35.2 kW at the shaft. What is its efficiency?

  1. 46.8 %
  2. 88.0 %
  3. 12.0 %
  4. 13.6 %
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Correct answer: 88.0 %

Efficiency = output ÷ input × 100 = 35.2 ÷ 40 × 100 = 88.0 %.

Source: Computed, 6.1: Testing Motor Components

Practice motors

Questions last reviewed: 18 October 2026