A 200 V DC machine supplies 20 A at 200 V as a generator. The armature resistance is 0.2 Ω. If the machine is now operated as a motor at same terminal voltage and current but with the flux increased by 10%, the ratio of motor speed to generator speed is

Electrical Machines
A 200 V DC machine supplies 20 A at 200 V as a generator. The armature resistance is 0.2 Ω. If the machine is now operated as a motor at same terminal voltage and current but with the flux increased by 10%, the ratio of motor speed to generator speed is

0.96

0.95

0.87

1.06

0.96

0.95

0.87

1.06

ANSWER DOWNLOAD EXAMIANS APP

Electrical Machines
A 3- phase synchronous motor can operate over a wide range of power factors i.e. from lagging to leading power factor. This is achieved by

varying the speed.

changing the load.

varying the applied voltage.

changing the field excitation.

varying the speed.

changing the load.

varying the applied voltage.

changing the field excitation.

ANSWER DOWNLOAD EXAMIANS APP

Electrical Machines
Commutation in a DC machine may be explained as a process

by which electric current in a coil is reversed.

in which magnetic field is set up.

how alternate flux affects the main field flux.

by virtue of which emf is induced in the armature conductors.

by which electric current in a coil is reversed.

in which magnetic field is set up.

how alternate flux affects the main field flux.

by virtue of which emf is induced in the armature conductors.

ANSWER DOWNLOAD EXAMIANS APP

Electrical Machines
Swinburne's test is applicable to

DC shunt and level Compound motor.

DC series motor.

DC Shunt motor.

DC compound motor.

DC shunt and level Compound motor.

DC series motor.

DC Shunt motor.

DC compound motor.

ANSWER DOWNLOAD EXAMIANS APP

Electrical Machines
If an AC servomotor has one of its winding excited by AC, then voltage measured at the other winding with rotor running will be

zero.

constant independent of speed.

proportional to square of rotor speed.

proportional to rotor speed.

zero.

constant independent of speed.

proportional to square of rotor speed.

proportional to rotor speed.

ANSWER DOWNLOAD EXAMIANS APP

Electrical Machines
The armature mmf in a dc machine is 1. stationary with respect to field poles 2. stationary with respect to armature 3. rotating with respect to field poles 4. rotating with respect to armature From these, the correct answer is

2, 4

1, 4

1, 3

2, 3

2, 4

1, 4

1, 3

2, 3

ANSWER DOWNLOAD EXAMIANS APP

Electrical Machines

Electrical Machines A 200 V DC machine supplies 20 A at 200 V as a generator. The armature resistance is 0.2 Ω. If the machine is now operated as a motor at same terminal voltage and current but with the flux increased by 10%, the ratio of motor speed to generator speed is

Electrical Machines A 3- phase synchronous motor can operate over a wide range of power factors i.e. from lagging to leading power factor. This is achieved by

Electrical Machines Commutation in a DC machine may be explained as a process

Electrical Machines Swinburne's test is applicable to

Electrical Machines If an AC servomotor has one of its winding excited by AC, then voltage measured at the other winding with rotor running will be

Electrical Machines The armature mmf in a dc machine is 1. stationary with respect to field poles 2. stationary with respect to armature 3. rotating with respect to field poles 4. rotating with respect to armature From these, the correct answer is

Electrical Machines
A 200 V DC machine supplies 20 A at 200 V as a generator. The armature resistance is 0.2 Ω. If the machine is now operated as a motor at same terminal voltage and current but with the flux increased by 10%, the ratio of motor speed to generator speed is

Electrical Machines
A 3- phase synchronous motor can operate over a wide range of power factors i.e. from lagging to leading power factor. This is achieved by

Electrical Machines
Commutation in a DC machine may be explained as a process

Electrical Machines
Swinburne's test is applicable to

Electrical Machines
If an AC servomotor has one of its winding excited by AC, then voltage measured at the other winding with rotor running will be

Electrical Machines
The armature mmf in a dc machine is 1. stationary with respect to field poles 2. stationary with respect to armature 3. rotating with respect to field poles 4. rotating with respect to armature From these, the correct answer is