1
GATE EE 2010
+2
-0.6
A separately excited DC motor runs at 1500 rpm under no-load with 200 V applied to the armature. The field voltage is maintained at its rated value. The speed of the motor, when it delivers a torque of 5 Nm, is 1400 rpm as shown in the figure. The rotational losses and armature reaction are neglected. The armature resistance of the motor is,
A
$$2\;\Omega$$
B
$$3.4\;\Omega$$
C
$$4.4\;\Omega$$
D
$$7.7\;\Omega$$
2
GATE EE 2010
+2
-0.6
A separately excited DC motor runs at 1500 rpm under no-load with 200 V applied to the armature. The field voltage is maintained at its rated value. The speed of the motor, when it delivers a torque of 5 Nm, is 1400 rpm as shown in the figure. The rotational losses and armature reaction are neglected. For the motor to deliver a torque of 2.5 Nm at 1400 rpm the armature voltage to be applied is
A
125.5 V
B
193.3 V
C
200 V
D
241.7 V
3
GATE EE 2009
+2
-0.6
Figure shows the extended view of a $$2$$ pole $$dc$$ machine with $$10$$ armature conductors. Normal brush positions are shown by $$A$$ and $$B,$$ placed at the inter polar axis. If the brushes are now shifted, in the direction of rotation to $$A'$$ and $$B'$$ as shown, the voltage waveform $${V_{A'B'}}$$ will resemble
A
B
C
D
4
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
$$474$$ $$V$$
EXAM MAP
Medical
NEET