CS/B.Tech(PWE-New)/SEM-4/PWE-401/2012
2012
ELECTRICAL MACHINES
Time Allotted : 3 Hours Full Marks : 70
The figures in the margin indicate full marks.
Candidates are required to give their answers in their own words
as far as practicable.
GROUP – A
( Multiple Choice Type Questions )
1. Choose the correct alternatives for any ten of the following :
10x1 = 10
i) Which of the following windings is connected in series
with armature winding of DC machine ?
a) Series winding
b) Auxiliary winding
c) Compensating winding
d) Commutating pole winding.
ii) What happens if field winding of a running shunt motor
suddenly breaks open ?
a) Its speeds slows down
b) Its speed becomes dangerously high
c) It gives out sparks
d) It stops at once.
iii) If the connections of field winding of dc shunt motor is
changed
a) Motor will not run
b) It will run in same direction
c) It will run in opposite direction
d) Motor speed will change.
iv) A shunt generator can be self-excited
a) only if resistance of field circuit is less than critical
value
b) only if resistance of field circuit is greater than
critical value
c) irrespective of value of resistance of the field
circuit
d) none of these.