# An elliptical loop having resistance R, of 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-axis with angular frequency w, the average power loss in the loop due to Joule heating is :

Question:

An elliptical loop having resistance $R$, of 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 $x$-axis with angular frequency $\omega$, the average power loss in the loop due to Joule heating is :

1. $\frac{\pi^{2} a^{2} b^{2} B^{2} \omega^{2}}{2 R}$

2. zero

3. $\frac{\pi a b B \omega}{R}$

4. $\frac{\pi^{2} a^{2} b^{2} B^{2} \omega^{2}}{R}$

Correct Option: 1

JEE Main Previous Year 1 Question of JEE Main from Physics Electromagnetic Induction chapter.
JEE Main Previous Year Sep. 03, 2020 (I)

Solution:

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