"The polarity of induced emf is such that it tends to produce a current which opposes the change in magnetic flux that produced it." This statement is known as . . . . . . law.

$A$ coil having an area $A_0$ is placed in a magnetic field which changes from $B_0$ to $4B_0$ in a time interval $t$. The $e.m.f.$ induced in the coil will be

$A$ loop of irregular shape of conducting wire (as shown in the figure) is placed in a uniform magnetic field perpendicular to the plane of the paper. If the loop changes into a circular shape,the direction of the induced current will be:

$A$ coil of effective area $3 \,m^2$ is placed at right angles to a magnetic field of induction $0.05 \,Wb/m^2$. If the field is decreased to $20 \%$ of its original value in $10 \,s$, the e.m.f. induced in the coil will be: (in $\,mV$)

The magnetic flux through a circuit of resistance $R$ changes by an amount $\Delta \phi$ in time $\Delta t$. Then the total quantity of electric charge $Q$ which is passing during this time through any point of the circuit is given by:

The adjoining figure shows two different arrangements in which two square wire frames are placed in a uniform constantly decreasing magnetic field $B.$ The direction of induced current in the case $II$ is