A long solenoid of diameter $0.1\;{\rm{ m\; has\; 2}} imes {\rm{1}}{{\rm{0}}^4}$ turns per meter. At the centre of the solenoid, a coil of 100 turns and radius $0.01\;{\rm{ m}}$ is placed with its axis coinciding with the solenoid axis. The current in the solenoid reduces at a constant rate to ${\rm{0A\; from\; 4A \;in\; 0}}{\rm{.05\; s}}$. if the resistance of the coil is $10{\pi ^2}\Omega \,,$ the total charge flowing through the coil during this time is

Consider the statements:(I)If magnetic field, ${\rm{B = 0}}$, then magnetic flux is also zero.(II)If magnetic flux, $\phi = 0,$ then magnetic field is also zero.

A square loop of side $22\,\,cm$ is converted into circular loop in $0.4\,\,s$. A uniform magnetic field of $0.2\,\,T$ directed normal to the loop then the $emf$ induced in the loop is

According to Lenz’s law of electromagnetic induction

A varying magnetic flux linking a coil is given by $\phi = X{t^2}$. If at time $t = 3{\rm{ }}s$, the emf induced is ${\rm{9}}\,\,{\rm{V}}$, then the value of $X$ is

A coil of $40\,\,{\rm{\Omega }}$ resistance has ${\rm{100}}$ turns and radius $6\,\,mm$ is connected to ammeter of resistance of $160\,\,ohms$. Coil is placed perpendicular to the magnetic field. When coil is taken out of the field, $32\,\,\mu C$ charge flows through it. The intensity of magnetic field will be

If a copper ring is moved quickly towards south pole of a powerful stationary bar magnet, then

The magnetic flux linked with the coil varies with time as $\phi = 3\,{t^2} + 4\,t + 9$. the magnitude of the induced emf at ${\rm{2}}\,{\rm{s}}$ is

The net magnetic flux through a closed spherical surface enclosing a bar magnet is:

A magnet is brought towards a coil (i) speedly (ii) slowly, then the induced e.m.f/induced charge will be respectively

The magnetic flux across a loop of resistance $10\,{\rm{\Omega }}$ is given by $\phi = 5\,{t^2} - 4\,t + 1\,\,{\rm{weber}}$. How much current is induced in the loop after ${\rm{0}}.{\rm{2}}\,\,{\rm{sec}}$