1. | \(0\) | 2. | \(2\) weber |
3. | \(0.5\) weber | 4. | \(1\) weber |
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. \(8\)
A coil of resistance \(400~\Omega\) is placed in a magnetic field. The magnetic flux \(\phi\) (Wb) linked with the coil varies with time \(t\)(s) as \(\phi=50t^{2}+4.\) The current in the coil at \(t=2\) s is:
1. \(0.5\) A
2. \(0.1\) A
3. \(2\) A
4. \(1\) A
1. | increases continuously. |
2. | decreases continuously. |
3. | first increases and then decreases. |
4. | remains constant throughout. |
The figure shows planar loops of different shapes moving out of or into a region of a magnetic field which is directed normally to the plane of the loop away from the reader. Then:
1. | for the rectangular loop abcd, the induced current is clockwise. |
2. | for the triangular loop abc, the induced current is clockwise. |
3. | for the irregularly shaped loop abcd, the induced current is anti-clockwise. |
4. | none of these. |
A conducting circular loop is placed in a uniform magnetic field, \(B=0.025\) T with its plane perpendicular to the loop. The radius of the loop is made to shrink at a constant rate of \(1\) mm s-1. The induced emf, when the radius is \(2\) cm, is:
1. \(2\pi ~\mu\)V
2. \(\pi ~\mu\)V
3. \(\frac{\pi}{2}~\mu\)V
4. \(2 \mu \) V
1. | twice per revolution. |
2. | four times per revolution. |
3. | six times per revolution. |
4. | once per revolution. |