In an ac circuit, the current is given by \(i=5\sin(100t-\frac{\pi}{2})\) and the ac potential is \(V =200\sin(100 t)\) volt.
The power consumption is:
1. \(20\) W
2. \(40\) W
3. \(1000\) W
4. \(0\)
In an \(LCR\) circuit having \(L = 8.0~\text{H}\), \(C= 0.5~\mu\text{F}\) and \(R = 100~\Omega\) in series, what is the resonance frequency?
1. \(600\) radian/sec
2. \(600\) Hz
3. \(500\) radian/sec
4. \(500\) Hz
A circuit consists of \(3\) ohms of resistance and \(4\) ohms of reactance. The power factor of the circuit is:
1. | \(0.4\) | 2. | \(0.6\) |
3. | \(0.8\) | 4 | \(1.0\) |
The power factor of a good choke coil is:
1. Nearly zero
2. Exactly zero
3. Nearly one
4. Exactly one
In a series \(LCR\) circuit, resistance \(R=10~\Omega\) and the impedance \(Z=20~\Omega\).
The phase difference between the current and the voltage will be:
1. \(30^{\circ}\)
2. \(45^{\circ}\)
3. \(60^{\circ}\)
4. \(90^{\circ}\)
In the circuit shown in the figure, neglecting source resistance, the voltmeter and ammeter reading respectively will be:
1. \(0~\text{V}, 3~\text{A}\)
2. \(150~\text{V}, 3~\text{A}\)
3. \(150~\text{V}, 6~\text{A}\)
4. \(0~\text{V}, 8~\text{A}\)
An AC source of variable frequency \(f\) is connected to an \(LCR\) series circuit. Which of the following graphs represents the variation of the current \(I\) in the circuit with frequency \(f\)?
1. | 2. | ||
3. | 4. |
1. | \(0.67~\text{W}\) | 2. | \(0.78~\text{W}\) |
3. | \(0.89~\text{W}\) | 4. | \(0.46~\text{W}\) |
1. | \(5000\) | 2. | \(50\) |
3. | \(500\) | 4. | \(5\) |
Match List I (expression for current) with List II (rms value of current) and select the correct answer.
List I | List II | ||
(a) | \(I=I_0 \sin \omega t \cos \omega t\) | (i) | \(I_0\) |
(b) | \(I=I_0 \sin \left(\omega t+\frac{\pi}{3}\right)\) | (ii) | \(I_0/\sqrt{2}\) |
(c) | \(I_0(\sin \omega t+\cos \omega t)\) | (iii) | \(I_0e\) |
(d) | \(I=I_0(e)\) | (iv) | \(I_0/2\sqrt{2}\) |
A | B | C | D | |
1. | (iv) | (ii) | (i) | (iii) |
2. | (iv) | (ii) | (iii) | (i) |
3. | (ii) | (iv) | (iii) | (i) |
4. | (ii) | (iv) | (i) | (iii) |