A square loop of side $15 \mathrm{~cm}$ being moved towards right at a constant speed of 2 $\mathrm{cm} /…
A square loop of side $15 \mathrm{~cm}$ being moved towards right at a constant speed of 2 $\mathrm{cm} / \mathrm{s}$ as shown in figure. The front edge enters the $50 \mathrm{~cm}$ wide magnetic field at $t=$ 0 . The value of induced emf in the loop at $t=10 \mathrm{~s}$ will be :
$0.3 \mathrm{mV}$
zero
$4.5 \mathrm{mV}$
$3 \mathrm{mV}$
Solution
At $\mathrm{t}=10 \mathrm{sec}$ complete loop is in magnetic field therefore no change in flux
$\mathrm{e}=\frac{\mathrm{d} \phi}{\mathrm{dt}}=0$
$\mathrm{e}=0$ for complete loop