ells A, B and C of radii a, b and c (a < b < c) have surface charge densities + δ, -δ and + δ respectively

Question

Three concentric metallic shells A, B and C of  radii a, b and c (a < b < c) have surface charge  densities + δ, -δ and +  δ respectively as shown  in the figure.

If shells A and C are at the same potential, then obtain the relation between t]ne radli a,,b and c.

Answer 1

q_{A =}4πa² , q_B = - σ. 

4πb² ,qc = σ. 4πc²,

Putting the values of q_A and q_B,

We get   a+ b = c