Question

Two conducting shells of radius a and b are connected by a conducting wire as shown in the figure. The capacity of the system is 

• A. \(4\pi\varepsilon_0 \dfrac{ab}{b-a}\)
• B. \(4\pi\varepsilon_0 (a+b)\)
• C. zero
• D. infinite

Hint:

Capacitances add directly when conductors are at same potential.

Answer 1

The Correct Option is B

Step 1: When connected by wire, both shells are at same potential.
Step 2: Equivalent capacitance is sum of individual capacitances. C = 4πvarepsilon₀ a + 4πvarepsilon₀ b