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 |
 76%
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 |
 56%
Level 3: 35%-60%
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The phase difference between the current and voltage of LCR circuit in series combination at resonance is 

(1) 0

(2) π/2

(3) π

(4) –π

 74%
Level 2: 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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The power factor of an ac circuit having resistance (R) and inductance (L) connected in series and an angular velocity ω is 

(1) R/ωL

(2) R/(R2+ω2L2)1/2

(3) ωL/R

(4) R/(R2ω2L2)1/2

Subtopic:  Different Types of AC Circuits |
 89%
Level 1: 80%+
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In an LR-circuit, the inductive reactance is equal to the resistance R of the circuit. An e.m.f. E=E0cos(ωt) applied to the circuit. The power consumed in the circuit is:

(1) E02R

(2) E022R

(3) E024R

(4) E028R

Subtopic:  Different Types of AC Circuits |
Level 3: 35%-60%
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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 |
 87%
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 |
 78%
Level 2: 60%+
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Which of the following plots may represent the reactance of a series LC combination 

(1) a

(2) b

(3) c

(4) d

Subtopic:  Different Types of AC Circuits |
Level 3: 35%-60%
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In an ac circuit, I = 100 sin 200 πt. The time required for the current to achieve its peak value will be

1. 1100sec

2. 1200sec

3. 1300sec

4. 1400sec

Subtopic:  RMS & Average Values |
 54%
Level 3: 35%-60%
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