Electrical Machines
A frog leg winding is used in a DC machine to eliminate

 the use of compensating winding.
 reactance voltage produced due to communication.
  the use equalizer in lap winding.
 the use drum winding.

ANSWER DOWNLOAD EXAMIANS APP

Electrical Machines
If the applied voltage of a certain transformer is increased by 50% and the frequency is reduced by 50%, the maximum flux density will (assuming that the magnetic circuit remains unsaturated)

 changes to three times the original value
 changes to 1.5 times the original value
 changes to 0.5 times the original value
 remain the same as the original

ANSWER DOWNLOAD EXAMIANS APP

Electrical Machines
An alternator is feeding an infinite busbar. Its prime mover is suddenly shutdown. The alternator will

 continue to work as alternator but the direction of rotation will reverse.
 start working as induction motor.
 continue to work as synchronous motor with same direction of rotation.
 come to stand still.

ANSWER DOWNLOAD EXAMIANS APP