An aluminium ring $B$ faces an electromagnet $A$. The current $I$ through $A$ can be altered. Which of the following statements is correct?

$A$ coil having effective area '$A$' is held with its plane normal to a magnetic field of induction '$B$'. The magnetic induction is quickly reduced to $25\%$ of its initial value in $1 \text{ s}$. The e.m.f. induced in the coil (in volt) will be

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

$A$ coil of resistance $8 \Omega$,number of turns $250$,and area $120 \ cm^2$ is placed in a uniform magnetic field of $2 \ T$ such that the plane of the coil makes an angle of $\frac{\pi}{6}$ with the direction of the magnetic field. In a time of $100 \ ms$,the coil is rotated until its plane becomes parallel to the direction of the magnetic field. The current induced in the coil is (in $A$)

The figure shows the north pole of a magnet moving away from a thick conducting loop containing a capacitor. The excess positive charge will arrive on

In a circuit with a coil of resistance $2\, \Omega$,the magnetic flux changes from $2.0\, Wb$ to $10.0\, Wb$ in $0.2\, s$. The charge that flows in the coil during this time is..........$C$.