The figure shows a square loop \(L\) with a side length of \(5~\text{cm},\) which is connected to a network of resistances. The entire setup is moving to the right with a constant speed of \(1~\text{cm/s}.\) At a certain instant, a part of the loop \(L\) is in a uniform magnetic field of \(1~\text{T},\) perpendicular to the plane of the loop. If the resistance of the loop is \(1.7~\Omega,\) the current in the loop at that instant will be close to:


1. \(115~\mu \text{A}\)
2. \(150~\mu \text{A}\)
3. \(170~\mu \text{A}\)
4. \(60~\mu \text{A}\)

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A circular coil of radius \(10\) cm is placed in a uniform magnetic field of \(3.0\times 10^{-5}~\mathrm{T}\) with its plane perpendicular to the field initially. It is rotated at constant angular speed about an axis along the diameter of coil and perpendicular to magnetic field so that it undergoes half of rotation in \(0.2\) s. The maximum value of EMF induced (in \(\mu V\)) in the coil will be close to:
1. \(5\)
2. \(10\)
3. \(15\)
4. \(20\)

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An elliptical loop with resistance \(R,\) semi-major axis \(a,\) and semi-minor axis \(b\) is placed in a magnetic field as shown in the figure. If the loop is rotated about the \(x\text-\)axis with an angular frequency \(\omega,\) the average power loss in the loop due to Joule heating is:

                                
1. zero

2. \( \dfrac{\pi^2 {a}^2 {b}^2 {B}^2 \omega^2}{R} \)

3. \(\dfrac{\pi^2 {a}^2 {b}^2 {B}^2 \omega^2}{2 R} \)

4. \(\dfrac{\pi {abB}\omega}{R} \)

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An infinitely long straight wire carrying current \(I\), one side opened rectangular loop and a conductor \(C\) with a sliding connector are located in the same plane, as shown in the figure. The connector has length \(l\) and resistance \(R\). It slides to the right with a velocity \(v\). The resistance of the conductor and the self inductance of the loop are negligible. The induced current in the loop, as a function of separation \(r\), between the connector and the straight wire is:

  
1. \( \frac{\mu_0}{\pi} \frac{I v l}{R r} \)
2. \( \frac{\mu_0}{2 \pi} \frac{I v l}{R r} \)
3. \(\frac{2 \mu_0}{\pi} \frac{I v l}{R r} \)
4. \( \frac{\mu_0}{4 \pi} \frac{I v l}{R r} \)

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A circular coil of \(1000\) turns each with an area of \(1~\text{m}^2\) is rotated about its vertical diameter at the rate of one revolution per second in a uniform horizontal magnetic field of \(0.07~\text{T}\). The maximum voltage generation will be:
1. \(220~\text{V}\)
2. \(330~\text{V}\)
3. \(440~\text{V}\)
4. \(550~\text{V}\)
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A metallic conductor of length \(1~\text{m}\) rotates in a vertical plane parallel to the east-west direction about one of its ends with an angular velocity of \(5~\text{rad/s}\). If the horizontal component of earth's magnetic field is \(0.2\times10^{-4}~\text{T}\), then emf induced between the two ends of the conductor is:
1. \(5~\mu\text{V}\)
2. \(50~\mu\text{V}\)
3. \(5~\text{mV}\)
4. \(50~\text{mV}\)
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A metallic rod of length \(20~\text{cm}\) is placed in a North-South direction and is moved at a constant speed of \(20~\text{m/s}\) towards the East. The horizontal component of the Earth's magnetic field at that place is \(4\times 10^{-3}~\text{T}\) and the angle of dip is \(45^{\circ}\). The emf induced in the rod is:
1. \(12~\text{V}\)
2. \(14~\text{V}\)
3. \(16~\text{mV}\)
4. \(18~\text{V}\)
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A metal rod of length \(1\) m is moving perpendicular to its length with \(8\) m/s velocity along the positive \(x\text-\)axis. A magnetic field \(B=2~\text{T}\) exists perpendicular to the plane of motion. The EMF induced between the two ends of the rod is:
1. \(16~\text{V}\) 
2. \(0~\text{V}\)
3. \(8~\text{V}\) 
4. \(4~\text{V}\)
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The EMF generated in a moving rod within a uniform magnetic field \(B\) is \(0.08~\text{V}.\) The speed \((v)\) of the rod is:
1. \(1\) m/s 2. \(2\) m/s
3. \(3\) m/s 4. \(4\) m/s
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A cube with side length \(25~\text{cm}\) is moving with a uniform velocity of \(8~\text{m/s}\) in the positive \(y\)-direction, as shown in the figure. The cube is placed in a uniform magnetic field of \(1~\text{T},\) which is directed along the negative \(z\)-axis. The magnitude of the induced EMF across the opposite faces of the cube is:
1. \(2~\text{V}\) 2. \(4~\text{V}\)
3. \(8~\text{V}\) 4. \(6~\text{V}\)
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