## Electrical Machines In a DC compound motor the field regulator is provided to

limit the armature current.
control the armature flux.
control the field flux.
demagnetize the field partially.

## Electrical Machines A 250 volt dc series motor having an armature resistance of 0.2 Ω takes a load current of 60 A. What will be the torque produced at the shaft of the motor? Consider brush drop of 1V.

133.22 N-m
can not be determined.
266.20 N-m.
234.76 N-m.

## Electrical Machines In the V curve shown in figure below for a synchronous motor, the parameter of Y and X coordinates are, respectively

Armature current and field current.
Torque and field current.
Armature current and torque.
Power factor and field current.

AC generator
DC generator
DC motor
induction motor

## Electrical Machines In shunt dc motor the direction of rotation of the motor will reversed. When

only armature terminals are reversed.
none of above.
either field terminals are reversed or armature terminals are reversed.
only field terminals are changed.

## Electrical Machines What happens if fifth multiples of harmonics is given to induction motor?

It will rotates in normal operation.
It will rotates in reverse direction.
Fail to start.
Either short circuit or open circuit occurs.