Question

A parallel plate condenser of capacity $1nF$ is connected to a battery of emf $2v$ though a resistance of $1M\Omega$. The displacement current after ${10}^{-3}\sec$ is:

• A. $0.37\mu A$
• B. $0.74\mu A$
• C. $1.48\mu A$
• D. $0.175\mu A$

Answer 1

The correct option is B $0.74\mu A$

$I=\frac{dq}{dt}=\frac{v}{R}{e}^{-t/RC}$
$=\frac{2}{1\times {10}^6}e$
$=\frac{2}{{10}^6}{e}^{-1}=\frac{2}{{10}^6}\times 0.3678$
$=0.7357\times {10}^{-3}\times {10}^{-6}$
$=0.7357\pi A$