Electrical Machines
The heat transfer by convection in a transformer least depends on

 surface area.
 temperature difference.
 air velocity.
  color of the paint.

ANSWER DOWNLOAD EXAMIANS APP

Electrical Machines
Cogging in induction motor occurs when

 number of stator teeth - number of rotor teeth = even number.
 number of stator teeth - number of rotor teeth = odd number.
 number of stator teeth - number of rotor teeth = 0.
 number of stator teeth - number of rotor teeth = negative number.

ANSWER DOWNLOAD EXAMIANS APP

Electrical Machines
For an ideal transformer the winding should have

 equal resistance on primary and secondary side
 minimum resistance on primary side and maximum resistance on secondary side
 no ohmic resistance on either side
 maximum resistance on primary side and least resistance on secondary side

ANSWER DOWNLOAD EXAMIANS APP

Electrical Machines
In a 3 - Φ induction motor

  power factor at starting is high as compared to that while running.
  power factor at starting is low as compared to that while running.
  power factor at starting in the same as that while running.
  none of them.

ANSWER DOWNLOAD EXAMIANS APP