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Answer :

The mechanical power developed by a shunt motor will be maximum when the ratio of back e.m.f. to applied voltage is 0.5.

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Last Answer : In case of D.C. shunt motors the speed is dependent on back e.m.f. only because flux is practically constant in D:C. shunt motors.

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.

Last Answer : The armature may burn if the back e.m.f. of a D.C. motor vanishes suddenly.

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

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Last Answer : The back emf of synchronous motor depends on load angle.

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Last Answer : In a d.c. motor, the mechanical output power actually comes from electrical input power.

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 : If the speed of a D.C. shunt motor is increased, the back e.m.f. of the motor will increase.

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

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Description : A 240 V, dc shunt motor draws 15 A while supplying the rated load at a speed of 80 rad/s. The armature resistance is 0.5 W and the field winding resistance is 80 W. The net Voltage across armature resistance at the time of plugging will be

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Description : A 200 V dc shunt motor is running at 1000 rpm and drawing a current of 10 A. Its armature winding resistance is 2 Ohm. It. is braked by plugging. The resistance to be connected in series with armature to restrict armature current to 10 A, is

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Last Answer : For a D.C. shunt motor if the excitation is changed torque will change but power will remain constant.

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Last Answer : The armature torque of the D.C. shunt motor is proportional to armature current.

Last Answer : As the load is increased the speed of D.C. shunt motor will reduce slightly.

Last Answer : In a D.C. shunt motor, speed is independent of armature current.

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Description : Why does the speed of a DC shunt motor decrease as the load increases?

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