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If the DC machine is held constant at 3000 rpm. The DC voltage is 250V. If the field is held constant with 250V. Is this machine generator or motor?

If the DC machine is held constant at 3000 rpm. The DC voltage is 250V. If the field is held constant with 250V. Is this machine generator or motor? Correct Answer Motor

From the speed and emf relation, E = 250*2950/3000 = 245.8 V This is less than the terminal voltage. Hence it is a motor.

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