A series LCR circuit is connected to an ac voltage source. When L is removed from the circuit, the phase difference between current and voltage is $${\pi \over 3}$$. If instead C is
removed from the circuit, the phase difference is again $${\pi \over 3}$$
between current and voltage. The power factor of the circuit is :
A
0.5
B
1.0
C
$$ - $$
1.0
D
zero
2
NEET 2018
MCQ (Single Correct Answer)
+4
-1
The magnetic potential energy stored in a
certain inductor is 25 mJ, when the current
in the inductor is 60 mA. This inductor is of
inductance
A
0.138 H
B
138.88 H
C
1.389 H
D
13.89 H
3
NEET 2018
MCQ (Single Correct Answer)
+4
-1
An inductor 20 mH, a capacitor 100 $$\mu $$F and
a resistor 50 $$\Omega $$ are connected in series across
a source of emf, V = 10 sin 314 t. The power
loss in the circuit is
A
0.79 W
B
0.43 W
C
2.74 W
D
1.13 W
4
NEET 2017
MCQ (Single Correct Answer)
+4
-1
Figure shows a circuit that contains three identical resistors with resistance R = 9.0 $$\Omega $$ each, two identical inductors with inductance $$L$$ = 2.0 mH each, and an ideal battery with emf $$\varepsilon = 18V$$. The current $$i$$ through the battery just after the switch closed is
