In dc machines, 1. reactance voltage is proportional to armature current 2.reactance voltage is proportional to core length 3.reactance voltage is due to self-flux of the coil undergoing commutation 4. armature-cross flux is neutralized by interpolar flux 5. interpolarmmf is more than armature mmf in the interpolar zone From these, the correct answer is

Electrical Machines
In dc machines, 1. reactance voltage is proportional to armature current 2.reactance voltage is proportional to core length 3.reactance voltage is due to self-flux of the coil undergoing commutation 4. armature-cross flux is neutralized by interpolar flux 5. interpolarmmf is more than armature mmf in the interpolar zone From these, the correct answer is

1, 2, 3, 4

2, 3, 4

1, 3, 5

1, 2, 5

1, 2, 3, 4

2, 3, 4

1, 3, 5

1, 2, 5

ANSWER DOWNLOAD EXAMIANS APP

Electrical Machines
The reduced air gap results in an increase

starting torque.

power factor.

breaking torque.

cost of operation.

starting torque.

power factor.

breaking torque.

cost of operation.

ANSWER DOWNLOAD EXAMIANS APP

Electrical Machines
A 230 V, 50 Hz, 4 pole single phase induction motor is rotating in the clockwise ( forward ) direction at a speed of 1425 rpm. If the rotor resistance at standstill is 7.8 ÃŽÂ©. Then the effective rotor resistance in the backward branch of the equivalent circuit will be

2 ÃŽÂ©.

8 ÃŽÂ©.

4 ÃŽÂ©.

10 ÃŽÂ©.

2 ÃŽÂ©.

8 ÃŽÂ©.

4 ÃŽÂ©.

10 ÃŽÂ©.

ANSWER DOWNLOAD EXAMIANS APP

Electrical Machines
The no load current in a transformer lags the applied voltage by

0°.

about 75°.

90°.

about 115°.

0°.

about 75°.

90°.

about 115°.

ANSWER DOWNLOAD EXAMIANS APP

Electrical Machines
Torque angle of a synchorous machine operating from a constant voltage bus is usually defined as the space angle between

Stator mmf wave and resultant flux density.

Stator mmf wave and resultant mmf wave.

Rotor mmf wave and stator mmf wave.

Rotor mmf wave and resultant flux density wave.

Stator mmf wave and resultant flux density.

Stator mmf wave and resultant mmf wave.

Rotor mmf wave and stator mmf wave.

Rotor mmf wave and resultant flux density wave.

ANSWER DOWNLOAD EXAMIANS APP

Electrical Machines
When applied rated voltage per phase is reduce to one half, the starting torque of three phase squirrel cage induction motor becomes

1/4 of the intial value

4 time the initial value

1/2 of the initial value

twice the initial value

1/4 of the intial value

4 time the initial value

1/2 of the initial value

twice the initial value

ANSWER DOWNLOAD EXAMIANS APP

Electrical Machines

Electrical Machines The reduced air gap results in an increase

Electrical Machines A 230 V, 50 Hz, 4 pole single phase induction motor is rotating in the clockwise ( forward ) direction at a speed of 1425 rpm. If the rotor resistance at standstill is 7.8 ÃŽÂ©. Then the effective rotor resistance in the backward branch of the equivalent circuit will be

Electrical Machines The no load current in a transformer lags the applied voltage by

Electrical Machines Torque angle of a synchorous machine operating from a constant voltage bus is usually defined as the space angle between

Electrical Machines When applied rated voltage per phase is reduce to one half, the starting torque of three phase squirrel cage induction motor becomes

Electrical Machines
The reduced air gap results in an increase

Electrical Machines
A 230 V, 50 Hz, 4 pole single phase induction motor is rotating in the clockwise ( forward ) direction at a speed of 1425 rpm. If the rotor resistance at standstill is 7.8 ÃŽÂ©. Then the effective rotor resistance in the backward branch of the equivalent circuit will be

Electrical Machines
The no load current in a transformer lags the applied voltage by

Electrical Machines
Torque angle of a synchorous machine operating from a constant voltage bus is usually defined as the space angle between

Electrical Machines
When applied rated voltage per phase is reduce to one half, the starting torque of three phase squirrel cage induction motor becomes