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

1.06

0.87

0.96

0.95

1.06

0.87

0.96

0.95

ANSWER DOWNLOAD EXAMIANS APP

Electrical Machines
In induction motor the 7th harmonic torque may make the motor rotate at (1 / 7)th synchronous speed. This is called

cogging.

resonance.

crawling.

harmonics.

cogging.

resonance.

crawling.

harmonics.

ANSWER DOWNLOAD EXAMIANS APP

Electrical Machines
What is the necessity of copper brushes in a dc motors?

To convert alternating supply current to direct current.

To increase the flux cutting by the rotor.

None of these.

To absorb the mechanical shocks produced during running condition.

To convert alternating supply current to direct current.

To increase the flux cutting by the rotor.

None of these.

To absorb the mechanical shocks produced during running condition.

ANSWER DOWNLOAD EXAMIANS APP

Electrical Machines
What will happen if the the supply terminals are reversed in case of a DC shunt motor?

The motor will run in reverse direction.

The motor will run much faster in the same direction.

The motor will run at its normal speed in the same direction as before.

The motor will stop.

The motor will run in reverse direction.

The motor will run much faster in the same direction.

The motor will run at its normal speed in the same direction as before.

The motor will stop.

ANSWER DOWNLOAD EXAMIANS APP

Electrical Machines
In a transformer zero voltage regulation is achieved at a load power factor which is

lagging

unity

leading

zero

lagging

unity

leading

zero

ANSWER DOWNLOAD EXAMIANS APP

Electrical Machines
Induction motors have the advantage of

all of below.

less cost.

less maintenance.

simple in construction.

all of below.

less cost.

less maintenance.

simple in construction.

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 In induction motor the 7th harmonic torque may make the motor rotate at (1 / 7)th synchronous speed. This is called

Electrical Machines What is the necessity of copper brushes in a dc motors?

Electrical Machines What will happen if the the supply terminals are reversed in case of a DC shunt motor?

Electrical Machines In a transformer zero voltage regulation is achieved at a load power factor which is

Electrical Machines Induction motors have the advantage of

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
In induction motor the 7th harmonic torque may make the motor rotate at (1 / 7)th synchronous speed. This is called

Electrical Machines
What is the necessity of copper brushes in a dc motors?

Electrical Machines
What will happen if the the supply terminals are reversed in case of a DC shunt motor?

Electrical Machines
In a transformer zero voltage regulation is achieved at a load power factor which is

Electrical Machines
Induction motors have the advantage of