A long solenoid has \(1000\) turns. When a current of \(4\) A flows through it, the magnetic flux linked with each turn of the solenoid is \(4\times 10^{-3}\) Wb. The self-inductance of the solenoid is:
1. \(3\) H
2. \(2\) H
3. \(1\) H
4. \(4\) H
1. | \(5\) H | 2. | \(2.5\) H |
3. | \(1.5\) H | 4. | \(2\) H |
Current in a circuit falls from \(5.0\) A to \(0\) A in \(0.1~\text{s}\). If an average emf of \(200\) V is induced, the self-inductance of the circuit is:
1. \(4\) H
2. \(2\) H
3. \(1\) H
4. \(3\) H
The back emf induced in a coil, when current changes from \(1\) ampere to zero in one milli-second, is \(4\) volts. The self-inductance of the coil is:
1. \(1~\text{H}\)
2. \(4~\text{H}\)
3. \(10^{-3}~\text{H}\)
4. \(4\times10^{-3}~\text{H}\)
1. | \(250\) J | 2. | \(125\) J |
3. | \(500\) J | 4. | \(100\) J |
The current \(i\) in an inductance coil varies with time \(t\) according to the graph shown in the figure. Which one of the following plots shows the variation of voltage in the coil with time?
1. | 2. | ||
3. | 4. |
A \(10\) H inductor carries a current of \(20\) A. How much ice at \(0^{\circ}\text{C}\) could be melted by the energy stored in the magnetic field of the inductor?
Latent heat of ice is \(2.26\times 10^{3}\) J/kg .
1. | \(0.08\) kg | 2. | \(8.8\) kg |
3. | \(0.88\) kg | 4. | \(0.44\) kg |
The number of turns in a coil of wire of fixed radius & length is \(600\) and its self-inductance is \(108\) mH. The self-inductance of a coil of \(500\) turns will be:
1. \(74\) mH
2. \(75\) mH
3. \(76\) mH
4. \(77\) mH
A coil is wound of a frame of rectangular cross-section. If the linear dimensions of the frame are doubled and the number of turns per unit length of the coil remains the same, then the self inductance increases by a factor of:
1. | \(6\) | 2. | \(12\) |
3. | \(8\) | 4. | \(16\) |
Calculate the self-inductance of a solenoid having \(1000\) turns and length \(1\) m. (The area of cross-section is \(7\) cm2 and \(\mu_r=1000).\)
1. \(888\) H
2. \(0.88\) H
3. \(0.088\) H
4. \(88.8\) H