The variation of EMF with time for four types of generators is shown in the figures. Which amongst them can be called AC voltage?

   
(a) (b)
   
(c) (d)
 
1. (a) and (d)
2. (a), (b), (c), and (d)
3. (a) and (b)
4.  only (a)
Subtopic:  AC Generator |
 72%
Level 2: 60%+
NEET - 2019
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Given below are two statements.
Assertion (A): When a current \(I=(3+4 \sin \omega t)\) flows in a wire, then the reading of
a dc ammeter connected in series is \(4\) units.
Reason (R): A dc ammeter measures only the value of the current amplitude.
 
1. Both (A) and (R) are True and (R) is the correct explanation of (A).
2. Both (A) and (R) are True but (R) is not the correct explanation of (A).
3. (A) is True but (R) is False.
4. Both (A) and (R) are False.
Subtopic:  AC vs DC |
 61%
Level 2: 60%+
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The instantaneous value of current in an AC circuit is \(I = 2\sin\left(100\pi t +\dfrac{\pi}{3}\right)~\text{A}\). The current will be maximum for the first time at:

1. \(t = \dfrac{1}{100}s\) 2. \(t = \dfrac{1}{200}s\)
3. \(t = \dfrac{1}{400}s\) 4. \(t = \dfrac{1}{600}s\)
Subtopic:  RMS & Average Values |
 65%
Level 2: 60%+
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A \(100~\Omega\) resistor is connected to a \(220~\text{V}\), \(50~\text{Hz}\) \(\text{AC}\) supply. The net power consumed over a full cycle is:
1. \(484~\text{W}\) 2. \(848~\text{W}\)
3. \(400~\text{W}\) 4. \(786~\text{W}\)
Subtopic:  Power factor |
 87%
Level 1: 80%+
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\(10~\mu\text F\) capacitor is connected to a \(210~\text V,50~\text{Hz}\) source as shown in the figure. The peak current in the circuit is nearly \((\pi = 3.14)\):

1. \(0.93~\text A\)
2. \(1.20~\text A\)
3. \(0.35~\text A\)
4. \(0.58~\text A\)
Subtopic:  RMS & Average Values |
 56%
Level 3: 35%-60%
NEET - 2024
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If the RMS current in a \(50~\text{Hz}\) AC circuit is \(5~\text{A}\), the value of the current \(\dfrac{1}{300}~\text{s}\) after its value becomes zero is:

1. \(5\sqrt2~\text{A}\) 2. \(5\sqrt{\dfrac32}~\text{A}\)
3. \(\sqrt{\dfrac56}~\text{A}\) 4. \(\dfrac{5}{\sqrt2}~\text{A}\)
Subtopic:  Different Types of AC Circuits |
 67%
Level 2: 60%+
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An alternating voltage \(V=V_0\sin(\omega t)\) is applied across a circuit. As a result, a current \(I=I_0\sin\Big(\omega t+\dfrac{\pi}{2}\Big)\) flows in it. The power consumed per cycle is:
1. \(\dfrac{V_0I_0}{2}\) 2. \(\dfrac{V_0I_0}{\sqrt2}\)
3. \(\sqrt2V_0I_0\) 4. zero
Subtopic:  Power factor |
 77%
Level 2: 60%+
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The variation of an alternating current; \(I=I_0 \mathrm{sin}(\omega t)\) with time \((t)\) is shown in the figure below. The average value of the current for the half-cycle will be: 

1. \(\dfrac{I_{0}}{\pi}\)
2. \(\dfrac{I_{0}}{2}\)
3. \(\dfrac{2 I_{0}}{\pi}\)
4. \(\dfrac{I_{0}}{2 \pi}\)
Subtopic:  RMS & Average Values |
 67%
Level 2: 60%+
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An alternating current given by \(I=I_0~\sin\omega t+I_0~\cos\omega t\) flows through a circuit. The RMS current is:
1. \(I_0\) 2. \(\dfrac{I_0}{\sqrt2}\)
3. \(\sqrt2I_0\) 4. zero
Subtopic:  RMS & Average Values |
 50%
Level 3: 35%-60%
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A light bulb is rated at \(100~\text W\) for a \(220~\text V\) AC supply. The peak voltage of the source is:
1. \(220~\text V\)
2. \(110~\text V\)
3. \(311~\text V\)
4. \(100~\text V\)

Subtopic:  RMS & Average Values |
 75%
Level 2: 60%+
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