A coil of inductance 1 H and resistance 100 Ω is connected to a battery of 6 V. Determine approximately: (a) The time elapsed before the current…

A coil of inductance $\displaystyle 1$ H and resistance $\displaystyle 100 \Omega$ is connected to a battery of $\displaystyle 6$ V . Determine approximately :

The time elapsed before the current acquires half of its steady - state value.

The energy stored in the magnetic field associated with the coil at an instant $\displaystyle 15$ ms after the circuit is switched on. (Given $\displaystyle \ln 2=0.693, \mathrm{e}^{-3 / 2}=0.25$ )