A coil of area 10   m 2 is placed in a uniform magnetic field of 0 . 3 k lb. m - 2 , with its plane…

Magnetic flux is given by $\varphi =BA\cos \left(\theta \right)$

$e=-\frac{∆\varphi }{∆t}=-\frac{{\varphi }_2-{\varphi }_1}{t_2-t_1}$

case $\mathrm{i}$ : for $0° \mathrm{to} 90°$ position

$e=-\frac{BA\cos \left(90\right)-BA\cos \left(0\right)}{t_2-t_1}=\frac{0.3\times 10}{2}=\frac{3}{2}\mathrm{mV}$

case $\mathrm{ii}$ : for $90° \mathrm{to} 180°$ position

$e=-\frac{BA\cos \left(180\right)-BA\cos \left(90\right)}{t_2-t_1}=\frac{0.3\times 10}{2}=\frac{3}{2}\mathrm{mV}$

case $\mathrm{iii}$ : for $180° \mathrm{to} 270°$ position

$e=-\frac{BA\cos \left(270\right)-BA\cos \left(180\right)}{t_2-t_1}=-\frac{0.3\times 10}{2}=-\frac{3}{2}\mathrm{mV}$

case $\mathrm{iv}$ : for $270° \mathrm{to} 360°$ position

$e=-\frac{BA\cos \left(360\right)-BA\cos \left(270\right)}{t_2-t_1}=-\frac{0.3\times 10}{2}=-\frac{3}{2}\mathrm{mV}$