In the circuit shown below, what will be the readings of the voltmeter and ammeter?
             

1. \(800~\text{V}, 2~\text{A}\)
2. \(300~\text{V}, 2~\text{A}\)
3. \(220~\text{V}, 2.2~\text{A}\)
4. \(100~\text{V}, 2~\text{A}\)

Subtopic:  Different Types of AC Circuits |
 88%
Level 1: 80%+
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The diagram shows a capacitor C and a resistor R connected in series to an ac source. V1 and V2 are voltmeters and A is an ammeter:

Consider now the following statements

I. Readings in A and V2 are always in phase

II. Reading in V1 is ahead in phase with reading in V2

III. Readings in A and V1 are always in phase

Which of these statements is/are correct?

1. I only

2. II only

3. I and II only

4. II and III only

Subtopic:  Different Types of AC Circuits |
 57%
Level 3: 35%-60%
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In the circuit shown in figure neglecting source resistance the voltmeter and ammeter reading will respectively, will be 

1. 0V, 3A

2. 150V, 3A

3. 150V, 6A

4. 0V, 8A

Subtopic:  Different Types of AC Circuits |
 86%
Level 1: 80%+
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In the circuit shown in the figure, the ac source gives a voltage V=20cos(2000 ​t). Neglecting source resistance, the voltmeter and ammeter reading will be: 

1. 0V, 0.47A

2. 1.68V, 0.47A

3. 0V, 1.4 A

4. 5.6V, 1.4 A

Subtopic:  RMS & Average Values |
Level 3: 35%-60%
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An ac source of angular frequency \(\omega\) is fed across a resistor \(r\) and a capacitor \(C\) in series. \(I\) is the current in the circuit. If the frequency of the source is changed to \(\frac{\omega}{3}\) (but maintaining the same voltage), the current in the circuit is found to be halved. Calculate the ratio of reactance to resistance at the original frequency \(\omega\).

1. \(\sqrt{\dfrac{3}{5}}\) 2. \(\sqrt{\dfrac{2}{5}}\)
3. \(\sqrt{\dfrac{1}{5}}\) 4. \(\sqrt{\dfrac{4}{5}}\)
Subtopic:  Different Types of AC Circuits |
 64%
Level 2: 60%+
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For a series \(RLC\) circuit, \(R = X_L = 2X_C.\) The impedance of the circuit and phase difference between \(V\) and \(i\) will be: 
1. \(\frac{\sqrt{5} R}{2} ,\tan^{- 1} \left(2\right)\) 2. \(\frac{\sqrt{5} R}{2} , \tan^{- 1} \left(\frac{1}{2}\right)\)
3. \(\sqrt{5} X_{C} ,\tan^{- 1} \left(2\right)\) 4. \(\sqrt{5} R , \tan^{- 1} \left(\frac{1}{2}\right)\)
Subtopic:  Different Types of AC Circuits |
 72%
Level 2: 60%+
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In the adjoining ac circuit the voltmeter whose reading will be zero at resonance is

1. V1

2. V2

3. V3

4. V4

Subtopic:  Different Types of AC Circuits |
 85%
Level 1: 80%+
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In the adjoining figure, the impedance of the circuit will be:

(1) 120 ohm

(2) 50 ohm

(3) 60 ohm

(4) 90 ohm

Subtopic:  Different Types of AC Circuits |
Level 3: 35%-60%
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In a series \(LCR\) circuit, which one of the following curves represents the variation of impedance \((Z)\) with frequency \((f)\)?

1. 2.
3. 4.
Subtopic:  Different Types of AC Circuits |
 57%
Level 3: 35%-60%
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The variation of the instantaneous current \((I)\) and the instantaneous emf \((E)\) in a circuit are shown in the figure. Which of the following statements is correct?

         

1. The voltage lags behind the current by \(\frac{\pi}{2}\).
2. The voltage leads the current by \(\frac{\pi}{2}\).
3. The voltage and the current are in phase.
4. The voltage leads the current by \(\pi\).
Subtopic:  RMS & Average Values |
 80%
Level 1: 80%+
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