Question

Two capacitors $C_1$ and $C_2$ are charged to $120\text{V}$ and $200\text{V}$, respectively. It is found that by connecting them together, the potential difference across each one can be made zero. Then:

• A. $3C_1+5C_2=0$
• B. $9C_1=4C_2$
• C. $5C_1=3C_2$
• D. $3C_1=5C_2$

Answer 1

The correct option is D $3C_1=5C_2$

Given,

$V_1=120\text{V}$, and $V_2=200\text{V}$

As we know that, $Q=CV$

$Q_1=120C_1.......\left(1\right)$

$Q_2=200C_2........\left(2\right)$

When capacitors are connected, potential can be made zero only if they have same charge.

$Q_1=Q_2$

$120C_1=200C_2$

$3C_1=5C_2$