Browse Questions

# A capacitor is charged and then made to discharge through a resistance. The time constant is $\tau$. In what time will the potential difference across the capacitor decrease by 10%

$\begin {array} {1 1} (A)\;\tau \: In (0.1) & \quad (B)\;\tau \: In (0.9) \\ (C)\;\tau \: In \bigg(\large\frac{10}{9}\bigg) & \quad (D)\;\tau \: In \bigg(\large\frac{11}{10}\bigg) \end {array}$

Direct substitution in the formula gives the answer.
Ans : (c)