Electrical Machines
The speed of a DC series motor is

 Proportional to the armature current.
 Proportional to the square of the armature current.
 Proportional to field current.
 Inversely proportional to the armature current.

ANSWER DOWNLOAD EXAMIANS APP

Electrical Machines
With the increase in speed of DC motor

 Back emf falls and line current increase.
 Both back emf as well as line current fall.
 Both back emf as well as line current increase.
  Back emf increase but line current falls.

ANSWER DOWNLOAD EXAMIANS APP

Electrical Machines
A DC shunt generator builds up to a voltage of 220 V at no load while running at its rated speed. If the speed of the generator is raised by 25% kepping the circuit conditions unaltered, then the Voltage to which the machine would build up will

 increase to a value greater than 1.25 times 220 V
 increase to 1.25 times 220 V
 not change and remain at 220 V
 increase to value lying between 220 V and 1.25 times 220 V

ANSWER DOWNLOAD EXAMIANS APP

Electrical Machines
In case of 3 - Φ IM, plugging means

  locking of rotor due to harmonics.
  interchanging two supply phases for quick stopping.
  starting the motor on load which is more than the rated load.
  pulling the motor directly on line without a rotor.

ANSWER DOWNLOAD EXAMIANS APP