The plates of a capacitor are charged to potential difference of $V\, volts$ and then connected across a resistor. The potential difference across the capacitor decreases exponentially with respect to time. After one second, the potential difference between the plates is $V/3$; then after two seconds from the start, the potential difference between the plates is
A$\frac{2V}{3}$
B$\frac{V}{6}$
C$\frac{V}{9}$
D$\frac{V}{3}$
Medium
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C$\frac{V}{9}$
c $\frac{V}{3}=V \cdot e^{-1 / R C}$ or $e^{-1 / R C}=\frac{1}{3}$
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