Question

Three identical, parallel conducting plates A, B and C are placed as shown. Switches $S_1$ and $S_2$ are open and can connect A and C to earth. When closed + Q charge is given to B. Then

• A. If $S_1$ is closed with $S_2$ open, a charge of amount Q will pass through $S_1$
• B. If $S_2$ is closed with $S_1$ open, a charge of amount Q will pass through $S_2$
• C. If $S_1$ and $S_2$ are closed together, a charge of amount Q/3 will pass through $S_1$ and a charge of amount 2Q/3 will pass through $S_2$
• D. All of the above statements are incorrect

Answer 1

Answer: (A), (B), (C)

The correct options are
A If $S_1$ is closed with $S_2$ open, a charge of amount Q will pass through $S_1$
B If $S_2$ is closed with $S_1$ open, a charge of amount Q will pass through $S_2$
C If $S_1$ and $S_2$ are closed together, a charge of amount Q/3 will pass through $S_1$ and a charge of amount 2Q/3 will pass through $S_2$

If $S_1$ is closed then Q will pass through $S_1$.
If only $S_2$ is closed

Q will pass through $S_2$.
If both are closed
$\frac{Q_1}{Q_2}=\frac{C_1}{C_2}=\frac{1}{2}{Q}_1=\frac{1}{3}Q{Q}_2=\frac{2}{3}Q$