# A small circular loop of wire of radius a is located at the centre of a much larger circular wire loop of radius b. The two loops are in the same plane. The outer loop of radius b carries an alternating current I = I o cos (wt). The emf induced in the smaller inner loop is nearly :

Question:

A small circular loop of wire of radius $a$ is located at the centre of a much larger circular wire loop of radius $b$. The two loops are in the same plane. The outer loop of radius $b$ carries an alternating current $\mathrm{I}=\mathrm{I}_{\mathrm{o}} \cos (\omega \mathrm{t})$. The emf induced in the smaller inner loop is nearly:

1. $\frac{\pi \mu_{0} I_{0}}{2} \cdot \frac{a^{2}}{b} \omega \sin (\omega t)$

2. $\frac{\pi \mu_{0} \mathrm{I}_{\mathrm{o}}}{2} \cdot \frac{\mathrm{a}^{2}}{\mathrm{~b}} \omega \cos (\omega \mathrm{t})$

3. $\pi \mu_{0} I_{0} \frac{a^{2}}{b} \omega \sin (\omega t)$

4. $\frac{\pi \mu_{0} I_{0} b^{2}}{a} \omega \cos (\omega t)$

Correct Option: 1

JEE Main Previous Year 1 Question of JEE Main from Physics Alternating Current chapter.
JEE Main Previous Year Online April 8, 2017

Solution:

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