Q. When the key $K$ is pressed at time $t = 0,$ which of the following statements about the current $I$ in the resistor $AB$ of the given circuit is true
A) $I = 2\ mA$ at all $t$
B) $I$ oscillates between $1\ mA$ and $2mA$
C) $I = 1\ mA$ at all $t$
D) At $t = 0,\ I = 2\ mA$ and with time it goes to $1\ mA$
Explanation
(d) At time $t = 0\ i.e.$ when capacitor is charging, current
$i = \frac{2}{1000} = 2mA$
When capacitor is full charged, no current will pass through it, hence current through the circuit
$i = \frac{2}{2000} = 1mA$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.