At the centre of a fixed large circular coil of radius R, a much smaller circular coil of radius r is placed. The two coils are concentric and are in the same plane. The larger coil carries a current I. The smaller coil is set to rotate with a constant angular velocity w about an axis along their common diameter. Calculate the emf induced in the smaller coil after a time t of its start of rotation.

Question:

At the centre of a fixed large circular coil of radius $R$, a much smaller circular coil of radius $\mathrm{r}$ is placed. The two coils are concentric and are in the same plane. The larger coil carries a current I. The smaller coil is set to rotate with a constant angular velocity $\omega$ about an axis along their common diameter. Calculate the emf induced in the smaller coil after a time $t$ of its start of rotation.

  1. $\frac{\mu_{0} I}{2 R} \omega r^{2} \sin \omega t$

  2. $\frac{\mu_{0} \mathrm{I}}{4 \mathrm{R}} \omega \pi \mathrm{r}^{2} \sin \omega \mathrm{t}$

  3. $\frac{\mu_{0} I}{2 R} \omega \pi r^{2} \sin \omega t$

  4. $\frac{\mu_{0} I}{4 R} \omega r^{2} \sin \omega t$


Correct Option: 3

JEE Main Previous Year 1 Question of JEE Main from Physics Electromagnetic Induction chapter.
JEE Main Previous Year Online April 15, 2018

Solution:

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