Three concentric metal shells A, B and C of respective radii and ( ) have surface…

PHYSICS · Single correct · A Level · Physics · Fields and their consequences · Fields and their consequences

Problem

Three concentric metal shells A, B and C of respective radii

a, b

and

c

(

a < b < c

) have surface charge densities

+\sigma, -\sigma

and

+\sigma

respectively. The potential of shell B is: (1)

\frac{\sigma}{\epsilon_0} \left[ \frac{a^2 - b^2}{a} + c \right]

(2)

\frac{\sigma}{\epsilon_0} \left[ \frac{a^2 - b^2}{b} + c \right]

(3)

\frac{\sigma}{\epsilon_0} \left[ \frac{b^2 - c^2}{b} + a \right]

(4)

\frac{\sigma}{\epsilon_0} \left[ \frac{b^2 - c^2}{c} + a \right]