$A$ coil of area $100 \, cm^2$ has $500$ turns. $A$ magnetic field of $0.1 \, Wb/m^2$ is perpendicular to the coil. The field is reduced to zero in $0.1 \, s$. The induced $e.m.f.$ in the coil is $...... \, V$.

In a magnetic field of $0.05\,T$,the area of a coil changes from $101\,cm^2$ to $100\,cm^2$ without changing the resistance,which is $2\,\Omega$. The amount of charge that flows during this period is:

The magnetic flux linked with a coil varies with time as $\Phi = 4t^2 + 3t + 7$. The magnitude of the induced e.m.f. at $t = 2 \ s$ is: (in $V$)

$A$ square loop of side $10 \ cm$ and resistance $0.5 \ \Omega$ is placed vertically in the east-west plane. $A$ uniform magnetic field of $0.10 \ T$ is set across the plane in the north-east direction. The magnetic field decreases to zero at $0.70 \ s$ at a steady rate. Then the magnitude of the induced current during this time interval will be . . . . . . .

$A$ flexible circular loop $20 \ cm$ in diameter lies in a magnetic field of magnitude $B = 1 \ T$,directed into the plane of the page as shown. The loop is pulled at the points indicated by the arrows,forming a loop of zero area in $0.314 \ s$. The average emf induced in the loop is.....$V$

Write the equation for the induced charge.