An inductor of \(20~\text{mH}\), a capacitor of \(100~\mu \text{F}\), and a resistor of \(50~\Omega\) are connected in series across a source of emf, \(V=10 \sin (314 t)\). What is the power loss in this circuit?
1. \( 0.79 ~\text{W} \)
2. \( 0.43 ~\text{W} \)
3. \( 2.74 ~\text{W} \)
4. \( 1.13 ~\text{W}\)
The potential differences across the resistance, capacitance and inductance are 80 V, 40 V and 100 V respectively in an L-C-R circuit. What is the power factor of this circuit?
1. 0.4
2. 0.5
3. 0.8
4. 1.0
A 100 resistance and a capacitor of 100 reactance are connected in series across a 220 V source. When the capacitor is 50% charged, the peak value of the displacement current is
(1) 2.2 A
(2) 11A
(3) 4.4A
(4) 11A
A small-signal voltage V(t)=Vo sinωt is applied across an ideal capacitor C
(1) over a full cycle, the capacitor C does not consume any energy from the voltage source
(2) current I(t) is in phase with voltage V(t)
(3) current I(t) leads voltage V(t) by 180°
(4) current I(t) lags voltage V(t) by 90°
Which of the following combinations should be selected for better tuning of an L-C-R circuit used for communication?
1. \(R=20~\Omega ,~L=1.5~H,~C=35~\mu F\)
2. \(R=25~\Omega ,~L=2.5~H,~C=45~\mu F\)
3. \(R=15~\Omega ,~L=3.5~H,~C=30~\mu F\)
4. \(R=25~\Omega ,~L=1.5~H,~C=45~\mu F\)
1. | over a full cycle, the capacitor C does not consume any energy from the voltage source. |
2. | current l(t) is in phase with voltage V(t). |
3. | current l(t) leads voltage V(t) by 180°. |
4. | current l(t), lags voltage V(t) by 90o. |