$A$ 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.....$V$

$A$ closed planar wire loop of area $A$ and arbitrary shape is placed in a uniform magnetic field of magnitude $B$,with its plane perpendicular to the magnetic field. The resistance of the wire loop is $R$. The loop is now turned upside down by $180^o$ so that its plane again becomes perpendicular to the magnetic field. The total charge that must have flowed through the wire ring in the process is

Some magnetic flux is changed through a coil of resistance $10 \, \Omega$. As a result,an induced current is developed in it,which varies with time as shown in the figure (assuming a triangular pulse with base $0.1 \, s$ and height $4 \, A$). The magnitude of the change in flux through the coil in Webers is:

The north pole of a long horizontal bar magnet is being brought towards a closed circuit consisting of a coil. The direction of the induced current produced in it is

Magnetic flux passing through a coil is initially $4 \times 10^{-4} \ Wb$. It reduces to $10 \%$ of its original value in $t$ seconds. If the induced emf is $0.72 \ mV$,then $t$ in seconds is:

The magnetic flux through a coil of resistance $R$ changes by an amount $\Delta \phi$ in time $\Delta t$. The total quantity of induced electric charge $Q$ is