# Time constant of a $RC$ circuit is $2/ln(2) s$. Capacitor is discharged at time $t = 0$. The ratio of charge on the capacitor at time $t = 2s$ and $t = 6s$ is

$\begin {array} {1 1} (A)\;3 : 1 & \quad (B)\;8:1 \\ (C)\;4:1 & \quad (D)\;2:1 \end {array}$

magnetic

Substitute $t = 2\: and \: t = 6$ sec in the formula for charging of a capacitor to get the answer.
Ans : (C)
edited Mar 14, 2014