When the current through an inductor is changed from $2 \,A$ to $6 \,A$ in time $2 \,s$, the emf induced in it is $3 \,V$. Then the inductance of the inductor is (in $\,H$)

The current in a coil changes from $3 \,A$ to $1 \,A$ in $0.1 \,s$ in a coil of self-inductance $8 \,mH$. The emf induced in the coil is

The current passing through a choke coil of $5 \, H$ is decreasing at the rate of $2 \, A/s$. The $e.m.f.$ developed across the coil is ....... $V$.

An inductor is connected to a direct voltage source through a switch. Which of the following statements is true regarding the induced electromotive force $(emf)$?

The current in a coil decreases from $1 \, A$ to $0.2 \, A$ in $10 \, s$. Calculate the coefficient of self-inductance if the induced $e.m.f.$ is $0.4 \, V$. (in $, H$)

The current in a coil of self-inductance $2.0 \, H$ is increasing according to $I = 2 \sin(t^2) \, A$. The amount of energy spent during the period when current changes from $0$ to $2 \, A$ is ...... $J$.