JEE Main · 2019 · 12 Jan 2019 · Shift 2 · Current Electricity

The charge on a capacitor plate in a circuit, as a function of time, is shown in the figure :

What is the value of current at

t = 4 s

Answer: (A)

Solution

The current charging a capacitor is the rate of change of its charge,

I = \frac{d q}{d t}

, which is simply the slope of the charge

-

time graph. At

t = 4

s the graph has levelled off to a constant charge, so its slope is zero and the current at that instant is zero.

JEE Main · 2019 · 12 Jan 2019 · Shift 2 · Single correct option