1
GATE EE 2008
+2
-0.6
A $$240V$$ $$dc$$ shunt motor draws $$15A$$ while supplying the rated load at a speed of $$80$$ $$rad/s$$. The armature resistance is $$0.5$$ $$ohm$$ and the field winding resistance is $$80$$ $$ohm.$$

The net voltage across the armature resistance at the time of plugging will be

A
$$6V$$
B
$$234$$ $$V$$
C
$$240$$ $$V$$
D
$$474$$ $$V$$
2
GATE EE 2006
+2
-0.6
A $$220V$$ $$DC$$ machine supplies $$20$$ $$A$$ at $$200V$$ as a generator. The armature resistance is $$0.2$$ ohm. If the machine is now operated as a motor at same terminal voltage and current but with the flux increased by $$10\% ,$$ the ratio of motor speed to generator speed is
A
$$0.87$$
B
$$0.95$$
C
$$0.96$$
D
$$1.06$$
3
GATE EE 2005
+2
-0.6
Two magnetic poles revolve around a stationary armature carrying two coils ($$c_1-c'_1$$ , $$c_2-c'_2$$ ) as shown in Figure. Consider the instant when the poles are in a position as shown. Identify the correct statement regarding the polarity of the induced emf at this instant in coil sides $$c_2$$ and $$c_1$$. A
$$\odot\;in\;c_1$$, no emf in c2
B
$$\otimes\;in\;c_1$$, no emf in c2
C
$$\odot\;in\;c_2$$, no emf in c1
D
$$\otimes\;in\;c_2$$, no emf in c1
4
GATE EE 2005
+2
-0.6
A 50 kW dc shunt motor is loaded to draw rated armature current at any given speed. When driven
(i) at half the rated speed by armature voltage control and
(ii) at 1.5 times the rated speed by field control, the respective output powers delivered by the motor are approximately
A
25 kW in (i) and 75 kW in (ii)
B
25 kW in (i) and 50 kW in (ii)
C
50 kW in (i) and 75 kW in (ii)
D
50 kW in (i) and 50 kW in (ii)
GATE EE Subjects
Electromagnetic Fields
Signals and Systems
Engineering Mathematics
General Aptitude
Power Electronics
Power System Analysis
Analog Electronics
Control Systems
Digital Electronics
Electrical Machines
Electric Circuits
Electrical and Electronics Measurement
EXAM MAP
Joint Entrance Examination