1
GATE EE 1999
MCQ (Single Correct Answer)
+2
-0.6
A DC shunt motor is running at 1200 rmp, when excited with 220 V DC. Neglecting the losses and saturation, the speed of the motor when connected to a 175 V DC supply is:
A
750 RPM
B
900 RPM
C
1050 RPM
D
1200 RPM
2
GATE EE 1999
MCQ (Single Correct Answer)
+2
-0.6
A 10 kVA, 400 V/200 V, single phase transformer with a percentage resistance of 3% and percentage reactance of 6% is supplying a current of 50 A to a resistive load. The value of the load voltage is:
A
194 V
B
390 V
C
192 V
D
196 V
3
GATE EE 1999
MCQ (Single Correct Answer)
+2
-0.6
A three phase alternator is wound with a 60 degree phase-spread armature windings and develops 300 kVA. If the armature is reconnected utilizing all the coils for single phase operation with a phase spread of 180 degrees, the new rating of the machine is
A
100 kVA
B
200 kVA
C
250 kVA
D
300 kVA
4
GATE EE 1999
MCQ (Single Correct Answer)
+1
-0.3
Higher synchronous reactance is preferred in the present day alternators, because one can have
A
reduced sub-transient currents
B
reduced harmonic currents
C
reduced transient currents
D
higher voltage regulation with load