A square loop with a side length of \(1~\text m\) and resistance of \(1~\Omega\) is placed in a uniform magnetic field of \(0.5~\text T.\) The plane of the loop is perpendicular to the direction of the magnetic field. The magnetic flux through the loop is:
1. zero 2. \(2\) Wb
3. \(0.5\) Wb 4. \(1\) Wb
Subtopic:  Magnetic Flux |
 68%
Level 2: 60%+
NEET - 2022
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In a coil of resistance \(10\) \(\Omega\), the induced current developed by changing magnetic flux through it is shown in the figure as a function of time. The magnitude of change in flux through the coil in Weber is:

1. \(2\) 2. \(6\)
3. \(4\) 4. \(8\)
Subtopic:  Magnetic Flux |
 69%
Level 2: 60%+
AIPMT - 2012
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A conducting circular loop of face area \(2.5 \times 10^{-3}~\text{m}^2\) is placed perpendicular to a magnetic field which varies as \(B=0.5~\text{sin}(100 \pi t)~\text{T}\). The magnitude of induced EMF at time \(t= 0~\text{s}\) is: 
1. \(0.125 \pi~ \text{mV}\) 2. \(125 \pi ~\text{mV}\)
3. \(125 \pi~\text{V}\) 4. \(12.5 \pi~\text{mV}\)
Subtopic:  Faraday's Law & Lenz Law |
 68%
Level 2: 60%+
NEET - 2024
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The magnetic flux linked to a circular coil of radius \(R\) is given by:
\(\phi=2t^3+4t^2+2t+5\) Wb.
What is the magnitude of the induced EMF in the coil at \(t=5\) s?

1. \(108\) V 2. \(197\) V
3. \(150\) V 4. \(192\) V
Subtopic:  Faraday's Law & Lenz Law |
 87%
Level 1: 80%+
NEET - 2022
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A \(800\) turn coil of effective area \(0.05~\text{m}^2\) is kept perpendicular to a magnetic field \(5\times 10^{-5}~\text{T}\). When the plane of the coil is rotated by \(90^{\circ}\)around any of its coplanar axis in \(0.1~\text{s}\), the emf induced in the coil will be:

1. \(0.02~\text{V}\) 2. \(2~\text{V}\)
3. \(0.2~\text{V}\) 4. \(2\times 10^{-3}~\text{V}\)
Subtopic:  Faraday's Law & Lenz Law |
 67%
Level 2: 60%+
NEET - 2019
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A long solenoid of diameter \(0.1\) m has \(2 \times 10^4\) turns per meter. At the center of the solenoid, a coil of \(100\) turns and radius \(0.01\) m is placed with its axis coinciding with the solenoid axis. The current in the solenoid reduces at a constant rate to \(0\) A from \(4\) A in \(0.05\) s. If the resistance of the coil is \(10\pi^2~\Omega\), then the total charge flowing through the coil during this time is:
1. \(16~\mu \text{C}\)
2. \(32~\mu \text{C}\)
3. \(16\pi~\mu \text{C}\)
4. \(32\pi~\mu \text{C}\)

Subtopic:  Faraday's Law & Lenz Law | Mutual Inductance |
 60%
Level 2: 60%+
NEET - 2017
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A uniform magnetic field is restricted within a region of radius \(r\). The magnetic field changes with time at a  rate \(\frac{dB}{dt}\). Loop \(1\) of radius \(R>r\) is enclosed within the region \(r\) and loop \(2\) of radius \(R\) is outside the region of the magnetic field as shown in the figure. Then, the emf generated is:
           

1. zero in loop \(1\) and zero in loop \(2\)
2. \(-\frac{dB}{dt}\pi r^2\) in loop \(1\) and zero in loop \(2\)
3.  \(-\frac{dB}{dt}\pi R^2\) in loop \(1\) and zero in loop \(2\)
4. zero in loop \(1\) and not defined in loop \(2\)
Subtopic:  Faraday's Law & Lenz Law |
 71%
Level 2: 60%+
NEET - 2016
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An electron moves on a straight-line path \(XY\) as shown. The \({abcd}\) is a coil adjacent to the path of electrons. What will be the direction of current if any, induced in the coil? 
  

1. \({abcd}\)
2. \({adcb}\)
3. The current will reverse its direction as the electron goes past the coil
4. No current included
Subtopic:  Faraday's Law & Lenz Law |
 74%
Level 2: 60%+
NEET - 2015
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A wire loop is rotated in a magnetic field. The frequency of change of direction of the induced emf is:
1. twice per revolution.
2. four times per revolution.
3. six times per revolution.
4. once per revolution.
Subtopic:  Faraday's Law & Lenz Law |
 74%
Level 2: 60%+
AIPMT - 2013
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A rod of length \(L\) rotates with a small uniform angular velocity \(\omega\) about its perpendicular bisector. A uniform magnetic field \(B\) exists parallel to the axis of rotation. The potential difference between the centre of the rod and an end is:
1. \(\Large\frac{B\omega L^2}{8}\) 2. \(\Large\frac{B\omega L^2}{2}\)
3. \(\Large\frac{B\omega L^2}{4}\) 4. zero
Subtopic:  Motional emf |
Level 3: 35%-60%
NEET - 2024
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