$A$ solenoid has an inductance of $60\, H$ and a resistance of $30\, \Omega$. If it is connected to a $100\, V$ battery,how long will it take for the current to reach $\frac{e - 1}{e} \approx 63.2\%$ of its final value?

In the given $L-R$ circuit,which of the following statements is correct?

$A$ coil of inductance $300\, mH$ and resistance $2\, \Omega$ is connected to a source of voltage $2\, V$. The current reaches half of its steady state value in $t$ seconds. Find the value of $t$. (in $, s$)

For the given circuit,the current $i$ through the battery when the key is closed and the steady state has been reached is .....$A$.

$A$ coil of inductance $40 \, H$ is connected in series with a resistance of $8 \, \Omega$ and the combination is joined to the terminals of a $2 \, V$ battery. The time constant of the circuit is ...... $s$.

In the circuit shown,the cell is ideal. The coil has an inductance of $4H$ and zero resistance. $F$ is a fuse of zero resistance and will blow when the current through it reaches $5A$. The switch is closed at $t = 0$. The fuse will blow after how much time?