A rectangular coil of 20 turns and area of cross section 25 cm² has a resistance of 100 ohm. If the magnetic field which is perpendicular to the plane of coil changes at the rate of 1000 tesla/ sec, the current in the coil is 
 

Given data: A rectangular coil $20\text{ turns }$and area of cross section $25\text{ sq.cm }$, resistance of $100 \mathrm{ohm}$.

Concept used: electromagnetic induction.

Detailed solution:

The propensity of a coil to resist internal current fluctuations is known as self-inductance.

$$\begin{gathered} \text{i}=\frac{\text{EMF}}{\text{R}} \\ =\frac{\text{nA}\frac{\text{db}}{\text{dt}}}{\text{R}} \\ =\frac{20\times .0025\times 1000}{100} \\ =0.5 \text{A} \end{gathered}$$

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