A coil of area A and N turns is rotating with angular velocity $\omega$ in a uniform magnetic field $\vec{B}$ about an axis perpendicular to $\vec{B}$. Magnetic flux $\varphi$ and induced $\operatorname{emf} \varepsilon$ across it, at an instant when $\vec{B}$ is parallel to the plane…

Question

A coil of area A and N turns is rotating with angular velocity $\omega$ in a uniform magnetic field $\vec{B}$ about an axis perpendicular to $\vec{B}$. Magnetic flux $\varphi$ and induced $\operatorname{emf} \varepsilon$ across it, at an instant when $\vec{B}$ is parallel to the plane of coil, are :

Aicharya · Accepted Answer

$\begin{aligned}
\phi & =\mathrm{BAN} \cdot \cos (\omega \mathrm{t}) \\ \varepsilon & =\frac{-\mathrm{d} \phi}{\mathrm{dt}}=\mathrm{BA} \omega \mathrm{~N} \cdot \sin (\omega \mathrm{t})
\end{aligned}$
When $B$ is parallel to plane, $\underline{\underline{\omega t}}=\frac{\pi}{2}$
$\Rightarrow \phi=0, \varepsilon=\mathrm{BA} \omega \mathrm{~N}$

A coil of area A and N turns is rotating with angular velocity \(\omega\) in a uniform magnetic field…

Solution