A coil of area $500 \mathrm{~cm}^{2}$ having 1000 turns is put perpendicular to a magnetic field of

Question

A coil of area $500 \mathrm{~cm}^{2}$ having 1000 turns is put perpendicular to a magnetic field of intensity $4 	imes 10^{-5}$ weber $/ \mathrm{m}^{2}$. If it is rotated by $180^{\circ}$ in 0.1 sec , the induced emf produced is\

Professor PC Thomas Classes · Answer

$\phi_{2}=\mathrm{BAN}$\  When rotated through $180^{\circ}$\ $\phi_{2}=-\mathrm{BAN}$\ $\mathrm{d} \phi=\phi_{1}-\phi_{2}$\ $=2$ BAN\ B = field = $4 	imes 10^{-5} \mathrm{~Wb} / \mathrm{m}^{2}$\ $\mathrm{A}=$ area of coil $=500 \mathrm{~cm}^{2}=500 	imes 10^{-4} \mathrm{~m}^{2}$\ $\mathrm{N}=$ total number of turns = 1000\ $\varepsilon=\frac{d \varphi}{d t}=\frac{2 B A N}{d t}=V$\