Lenz's law is expressed by the following formula (here $e$ = induced $e.m.f.$,$\phi$ = magnetic flux in one turn and $N$ = number of turns).

$A$ long solenoid of radius $2\, cm$ has $100\, turns/cm$ and carries a current of $5\, A$. $A$ coil of radius $1\, cm$ having $100\, turns$ and a total resistance of $20\, \Omega$ is placed inside the solenoid coaxially. The coil is connected to a galvanometer. If the current in the solenoid is reversed in direction,find the charge flown through the galvanometer.

$A$ square conducting loop is placed near an infinitely long current-carrying wire with one edge parallel to the wire as shown in the figure. If the current in the straight wire is suddenly halved, which of the following statements will be true? "The loop will .......".

$A$ flat circular coil has $100$ turns of wire of radius $10 \ cm$. $A$ uniform magnetic field exists in a direction perpendicular to the plane of the coil and it grows at a rate of $0.1 \ T \ s^{-1}$. The induced emf in the coil is:

$A$ coil of resistance $200 \Omega$ is placed in a magnetic field. If the magnetic flux $\phi$ (in weber) linked with the coil varies with time $t$ (in second) as per the equation $\phi = 50t^2 + 4$,then the current induced in the coil at a time $t = 2 \ s$ is (in $A$)

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: