In an induction coil with resistance,the induced emf will be maximum when

The $SI$ unit of self-inductance is:

What will be the self-inductance of a coil of $100$ turns if a current of $5 \ A$ produces a magnetic flux of $5 \times 10^{-5} \ Wb$?

An air-cored solenoid with length $30 \; cm$,area of cross-section $25 \; cm^{2}$ and number of turns $500$,carries a current of $2.5 \; A$. The current is suddenly switched off in a brief time of $10^{-3} \; s$. How much is the average back $emf$ induced (in $V$) across the ends of the open switch in the circuit? Ignore the variation in magnetic field near the ends of the solenoid.

The current $(I)$ in an inductor is varying with time $(t)$ as shown in the figure. Which of the following graphs shows the correct variation of voltage $(V)$ with time $(t)$ in the inductor?

The unit of inductance is