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

A circular coil of 600 turns with a radius of 5 cm is placed in a uniform magnetic field of $8 imes 10^{-5}\ T$ perpendicular to the plane of the coil. If the coil is rotated through $90^0$ about a diameter in 0.2 seconds, what is the average emf induced?

A circular coil of ${\rm{500}}$ turns of wire has an enclosed area of $0.1\,\,{m^2}$ per turn. It kept perpendicular to a magnetic field of induction $0.2\,\,T$ and rotated by ${180^0}$ about a diameter perpendicular to the field in $0.1\,\,\sec$. How much charge will pass when the coil is connected to a galvanometer with a combined resistance of $50\,\,ohms$

A coil of 75 turns and radius 0.012 m is placed at the center of a long solenoid with diameter 0.14 m and 18000 turns per meter, their axes aligned. The current in the solenoid decreases uniformly from 6 A to 0 A in 0.06 s. With a coil resistance of $9\pi^2\,\Omega$, find the total charge flowing through the coil.

A circular loop of radius $R$, carrying current $I$ lies in $xy -$plane with its centre at origin. The total magnetic flux through $xy$-plane is

Two identical coaxial circular loops carry current $i$ each circulating in the clockwise direction. If the loops are approaching each other, then

A coil having n turns and resistance $R\,\,{\rm{\Omega }}$ is connected with a galvanometer of resistance $4R\,\,{\rm{\Omega }}$. This combination is moved in time $t$ sec from a magnetic field ${W_1}\,{\rm{wb}}\,{\rm{ to}}\,\,{W_2}\,{\rm{wb}}$. The induced current in the circuit is

The flux associated with coil changes from ${\rm{1}}.{\rm{35}}\,\,{\rm{Wb}}$ to ${\rm{0}}.{\rm{79}}\,\,{\rm{Wb}}$ within $\frac{1}{{10}}s$. Then the charge produced by the earth coil, if resistance of coil is $7\,\Omega$ is

The north pole of a long bar magnet was pushed slowly into a short solenoid connected to a galvanometer. The magnet was held stationary for a few seconds with the north pole in the middle of the solenoid and then withdrawn rapidly. The maximum deflection of the galvanometer was observed when the magnet was

According to Lenz’s law of electromagnetic induction

A cylindrical bar magnet is kept along the axis of a circular coil. If the magnet is rotated about its axis, then