In the given circuit, the switch `K_2` is opened and the switch `K_1` is closed at time t=0. At time `t=t_0`, the switch `K_1` is opened and the switch `K_2` is simultaneously closed. Sketch the variation of the inductor current I with time.

Explanation

Between time t=0 and `t=t_0`, the equation for the inductor current `L(dI)/(dt)=E` or,`I=E/Lt`
For time `tget_0`, the equation for the inductor current, `L((dI)/(dt))=0`
or, `I=I(t_0)=(Et_0)/L`(constant)
Thus I increases linealy with a slope `E/L` for t=0 to `t=t_0`.
For time `tget_0`, I becomes a constant `(=(Et_0)/L)`.
THe variation of current (I) with time (t) is shown in Fig.2.40.