$A$ coil is placed perpendicular to a magnetic field of $5000 \,T$. When the field is changed to $3000 \,T$ in $2 \,s$, an induced emf of $22 \,V$ is produced in the coil. If the diameter of the coil is $0.02 \,m$, then the number of turns in the coil is:

If magnetic flux $\phi = (3t^2 - 2t + 5) \ Wb$,then what is the induced emf at $t = 2 \ s$?

If a coil of $40$ turns and area $4.0 \, cm^2$ is suddenly removed from a magnetic field,it is observed that a charge of $2.0 \times 10^{-4} \, C$ flows through the coil. If the resistance of the coil is $80 \, \Omega$,the magnetic flux density in $Wb/m^2$ is:

There are two coils $A$ and $B$ as shown in the figure. No current flows in $B$ if $A$ is at rest. Now,the coil $A$ is made to rotate about a vertical axis. At the shown instant $(t=0)$,what will be the direction of the current in coil $A$,when the induced current in coil $B$ is counterclockwise?

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

Magnetic flux in a circuit containing a coil of resistance $2\,\Omega$ changes from $2.0\,Wb$ to $10\,Wb$ in $0.2\,s$. The charge passed through the coil in this time is......$C$