When the armature of a D.C. motor rotates, e.m.f. induced is

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When the armature of a D.C. motor rotates, e.m.f. induced is back e.m.f.

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Last Answer : In a D.C. series motor, if the armature current is reduced by 50%, the torque of the motor will be equal to 25% of the previous value.

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As there is no back e.m.f. at the instant of starting a D.C. motor, in order to prevent...

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