# The mechanical power developed by the armature of a d.c. motor is equal to?

The mechanical power developed by the armature of a d.c. motor is equal to?

The mechanical power developed by the armature of a d.c. motor is equal to armature current multiplied by back e.m.f.

## Related questions

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Description : The synchronous motor which works on leading power factor and does not drive any mechanical load is called?

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Last Answer : In a D.C. shunt motor, under the conditions of maximum power, the current in the armature will be more than full-load current.

Description : The normal value of the armature resistance of a d.c. motor is?

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Last Answer : A synchronous motor has better power factor as compared to that of an equivalent induction motor. This is mainly because stator supply is not required to produce magnetic field.

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Description : If the load of the normally excited synchronous motor is increased the power factor will?

Last Answer : If the load of the normally excited synchronous motor is increased the power factor will become lagging.

Description : If the field of synchronous motor is under excited, power factor will be?

Last Answer : If the field of synchronous motor is under excited, power factor will be lagging.

Description : The synchronous motor will develop maximum power when the load angle is?

Last Answer : The synchronous motor will develop maximum power when the load angle is 900.

Last Answer : Yes, we can make the power factor of synchronous motor leading by adjusting its excitation.

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Description : A d.c. motor can be looked upon as d.c. generator with the power flow?

Last Answer : A d.c. motor can be looked upon as d.c. generator with the power flow reversed.

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Description : Explain the necessity of starter for D.C. motor. State various types of D.C. motor starter.

Last Answer : Necessity of Starter for D.C. Motor: Armature current is given by equation Ia = (V−Eb)/Ra i) If the motor is at standstill or rest, back emf Eb is zero (as Eb= ZNP/(60A), at start speed N ... . Types of D.C. motor starters: i) Two point starter ii)Three point starter iii) Four point starter

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Last Answer : Because if the load is increasing then the torque must also be increase. If not then the speed of motor will decrease.

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Description : The counter e.m.f. of a d.c. motor?

Last Answer : The counter e.m.f. of a d.c. motor helps in energy conversion.

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