If in a coil the rate of change of area is $5 \, m^2/ms$ and the current changes from $2 \, A$ to $1 \, A$ in $2 \times 10^{-3} \, s$. If the magnetic field is $1 \, T$,then the self-inductance of the coil is......$H$

The current through a choke coil increases from zero to $6 \ A$ in $0.3 \ s$ and an induced $e.m.f.$ of $30 \ V$ is produced. The inductance of the choke coil is ....... $H$.

Which of the following units denotes the dimensions $\frac{M L^2}{Q^2}$,where $Q$ denotes the electric charge?

An air-cored solenoid with length $20 \, cm$,area of cross-section $20 \, cm^2$,and number of turns $400$ carries a current of $2 \, A$. The current is suddenly switched off within $10^{-3} \, s$. The average back $emf$ induced across the ends of the open switch in the circuit is (ignore the variation in magnetic field near the ends of the solenoid) ........ $V$.

The unit of inductance is

If $R$ and $L$ represent respectively resistance and self-inductance,which of the following combinations has the dimensions of frequency?