For a series, LCR circuit quality factor is and potential difference across circuit . The potential difference across the inductor in resonance state will be:
1. Zero
2.
3.
4.
The ratio of current delivered by the battery just after the switch is closed to a long time after the switch closed is
What is the reading of the A.C voltmeter in the network as shown in the figure?
1. zero
2. 100 V
3. 200 V
4. 400 v
What is the value of the power factor for a parallel LC circuit at a frequency less than the resonance frequency?
1. Zero
2. 1
3. > 1
4.< 1
When an alternating voltage is given as; \(E = (6 \sin\omega t - 2 \cos \omega t)~\text V,\) what is its RMS value?
1. \(4 \sqrt 2 ~\text V\)
2. \(2 \sqrt 5 ~\text V\)
3. \(2 \sqrt 3 ~\text V\)
4. \(4 ~\text V\)
Current through an elements in ac circuit is said to be wattless, when the elements is
1. Pure inductor (L)
2. Pure capacitor (C)
3. Series L-C circuit
4. All of these
An LC circuit contains an inductor (L=25 mH) and a capacitor (C=25 mF) with an initial charge of Q0. At what time will the circuit have an equal amount of electrical and magnetic energy?
4. All of these
In which of the following circuits can the power factor be zero?
1. LC circuit
2. LCR circuit
3. Purely resistive circuit
4. Both (1) & (2)
The quality factor of the resonance circuit is given by (symbols have usual meanings)
In the given circuit, switch S is closed at t=0. After a long time, the iron rod is withdrawn from the inductor L. Then, the bulb
1. Glow with the same brightness
2. Glows more brightly
3. Gets dimmer
4. Stops glowing