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# 4. The excitation of a 414 V, 3-phase, delta-connected synchronous motor is such that that the...

4. The excitation of a 414 V, 3-phase, delta-connected synchronous motor is such that that the induced emf is 520 V. The impedance per phase is 0.5 + j 4 ohms. If the friction and iron losses are constant at 1,000 W, calculate the efficiency for maximum power output.

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