MotorsQuestion 1450 of 1506

A motor on a 60 Hz supply has a synchronous speed of 900 rpm. How many poles does it have?

16 poles
8 poles
6 poles
4 poles

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Correct answer: 8 poles

P = 120 × f ÷ Ns = 120 × 60 ÷ 900 = 8 poles.

Source: Computed, 13.2: Synchronous Motors

Questions last reviewed: 18 October 2026

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