1 and 2
1 and 3
1, 2 and 3
2 and 3

## Electrical Machines The following statements relate to compensating winding (CW) and interpole winding (IW) of a dc machine : 1. CW neutralizes the armature reaction under a pole pitch 2. IW is connected in series with armature circuit 3. IW produces mmf in the commutating zone only 4. CWmmf is directed along the brush axis 5. Mmf produced by IW is equal to armature mmf From these, the correct statements are

2, 3, 4
2, 3, 4, 5
1, 2, 3, 4 and 5
1, 3, 4, 5

## Electrical Machines If the speed of a dc motor increases with load torque, then it is a

differentially compounded motor
permanent magnet motor
comulatively compounded motor
series motor

## Electrical Machines If the field of a dc shunt motor gets opened while the motor is running, then the

armature will oscillate about original speed as the mean speed
motor will attain dangerously high speed
armature current will drop
motor will become slow.

## Electrical Machines A DC cumulatively compounded motor delivers rated load torque at rated speed. If the series field is short-circuited, then the armature current and speed will

increase and decrease respectively
both decrease
both increase
decrease and increase respectively