Exam

JEE Main

Year

2019

Date

11 January

Shift

Morning Shift

Subject

Physics

Chapter

Alternating Current

JEE Main 2019 · 11 January · Morning Shift · Physics · Alternating Current

In the circuit shown, the switch S_ 1 is closed at time t=0 and the...

In the circuit shown,

the switch $S_{1}$ is closed at time $t=0 and the switch$S_{2}$is kept open. At some later time \left(\mathrm{t}_{0}\right)$, the switch $\mathrm{S}_{1}$ is opened and $\mathrm{S}_{2}$ is closed. the behaviour of the current I as a function of time ' $\mathrm{t}$ ' is given by:

Step-by-step solution

The current will grow for the time $\mathrm{t}=0$ to $\mathrm{t}=\mathrm{t}_{0}$ and after that decay of current takes place.
Growth and decay of current is of exponential nature
$\mathrm{i}=\mathrm{i}_0\left(1-\mathrm{e}^{-\mathrm{t} / \mathrm{\tau}}\right) \rightarrow \text{ during growth }$
$\mathrm{i}=\mathrm{i}_{\max } \mathrm{e}^{-\mathrm{t} / \mathrm{\tau}} \rightarrow \text{ during decay }$