Question

A coil having number of turns $N$ and area $A$ is rotated in a uniform magnetic field $B$ with angular velocity $\omega$ ) about its diameter. Maximum e.m.f. induced in it is given by

• A. $N A B \omega$
• B. $\frac{N A B}{\omega}$
• C. $\frac{N A \omega}{B}$
• D. $\frac{B \omega}{N A}$

Answer 1

Answer: (A)

$\phi=N B A \cos \theta=N B A \cos \omega t$
$\varepsilon=-\frac{d \phi}{d t}$
$\varepsilon=N B A \omega \sin \omega t$
$\varepsilon_{\max }=N B A \omega$