GATE EE 2021 Set 1 — Question 28

NAT+1 / -0MediumPerformance CalculationsThree-Phase Induction MachinesElectrical Machines

Electrical Machines → Three-Phase Induction Machines → Performance Calculations

Last updated 5 September 2026

Question

The power input to a 500 V, 50 Hz, 6-pole, 3-phase induction motor running at 975 RPM is 40 kW. The total stator losses are 1 kW. If the total friction and windage losses are 2.025 kW, then the efficiency is______%.

N_s = \frac{120f}{P} = \frac{120 \times 50}{6} = 1000

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N_s = \frac{120f}{P} = \frac{120 \times 50}{6} = 1000

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