A \(220\) V, \(50\) Hz AC source is connected to an inductance of \(0.2\) H and a resistance of \(20\) ohms in series. How much current flows across the circuit?
1. \(10\) A
2. \(5\) A
3. \(33.3\) A
4. \(3.33\) A

Subtopic:  Different Types of AC Circuits |
 69%
Level 2: 60%+
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When a step-down transformer is connected to a \(2400\) volt line, the output load receives \(80\) amps of current. The ratio of the turns in the primary and secondary coils is \(20:1\). If transformer efficiency is \(100\%\), then the current flowing in the primary coil will be:
1. \(1600\) A 2. \(20\) A
3. \(4\) A 4. \(1.5\) A
Subtopic:  Transformer |
 79%
Level 2: 60%+
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A generator produces a voltage that is given by \(V = 240\sin(120t)\), where \(t\) is in seconds. The frequency and rms voltage are:
1. \(60\) Hz and \(240\) V
2. \(19\) Hz and \(120\) V
3. \(19\) Hz and \(170\) V
4. \(754\) Hz and \(70\) V
Subtopic:  RMS & Average Values |
 84%
Level 1: 80%+
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In an AC circuit, the current is given by; \(i=5\sin\left(100t-\frac{\pi}{2}\right)\) and the AC potential is \(V =200\sin(100 t)~\text V.\) The power consumption is:
1. \(20~\text W\)
2. \(40~\text W\)
3. \(1000~\text W\)
4. zero

Subtopic:  Power factor |
 86%
Level 1: 80%+
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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

Subtopic:  Different Types of AC Circuits |
 71%
Level 2: 60%+
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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 \(1.0\)
Subtopic:  Power factor |
 77%
Level 2: 60%+
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The power factor of a good choke coil is:

1. Nearly zero

2. Exactly zero

3. Nearly one

4. Exactly one

Subtopic:  Power factor |
 57%
Level 3: 35%-60%
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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. \(90^{\circ}\)

Subtopic:  Different Types of AC Circuits |
 84%
Level 1: 80%+
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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. \(0~\text{V}, 8~\text{A}\)

Subtopic:  Different Types of AC Circuits |
 88%
Level 1: 80%+
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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.
Subtopic:  Different Types of AC Circuits |
 79%
Level 2: 60%+
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