Question

The e.m.f. induced in a coil of wire, which is rotating in a magnetic field, does not depend on

• A. The angular speed of rotation
• B. The number of turns on the coil
• C. The area of the coil
• D. The resistance of the coil.

Answer 1

The correct option is D The resistance of the coil.

The induced in a coil of N turns is,

$\epsilon =-\frac{d}{dt}\left(\varphi \right)$

$\epsilon =-\frac{d}{dt}\left[NBA\cos \omega t\right]$

$\epsilon =NBA\omega \sin \omega t$

$\therefore$ Induced emf is independent of resistance of the coil.

<!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}--> Hence, $\left(D\right)$ is the correct answer.