The magnetic flux through a coil of resistance $10\,\Omega$ is changed by $\Delta \phi$ in $0.1\,s$. The resulting current in the coil varies with time as shown in the figure. Then,the magnitude $\left| \Delta \phi \right|$ is equal to (in weber):

$A$ coil having $100$ turns and an area of $1 \times 10^{-3} \ m^2$ is placed in a magnetic field of $1 \ Wb/m^2$. If the magnetic field is reversed,what is the total charge that flows through the circuit,given that the resistance of the circuit is $10 \ \Omega$?

The magnetic flux linked to a circular coil of radius $R$ is given by $\phi = 2t^3 + 4t^2 + 2t + 5 \; Wb$. The magnitude of the induced $emf$ in the coil at $t = 5 \; s$ is $.......... \; V$.

Discuss Faraday's experiment of two coils for the generation of electric current in a coil.

Consider a metal ring kept (supported by a cardboard) on top of a fixed solenoid carrying a current $I$ as per the figure. The centre of the ring coincides with the axis of the solenoid. If the current in the solenoid is switched off,what will happen to the ring?

$A$ copper ring having a cut such as not to form a complete loop is held horizontally and a bar magnet is dropped through the ring with its length along the axis of the ring as shown in figure. The acceleration of the falling magnet is ($g=$ acceleration due to gravity)