A spherical shell of radius `R_(1)` with a uniform charge q has a point charge `q_0` at its center. Find the work performed by the electric forces during the shell expansion from radius `R_(1)` to radius `R_(2)`.

Options

A. `W=(q(q_(0)+q//2))/(2piepsilon_(0))((1)/(R_(1))-(1)/(R_(2)))`
B. `W=(q(q_(0)+q//2))/(piepsilon_(0))((1)/(R_(1))+(1)/(R_(2)))`
C. `W=(q(q_(0)+q//2))/(4piepsilon_(0))((1)/(R_(1))-(1)/(R_(2)))`
D. `W=(q(q_(0)+q//2))/(4piepsilon_(0))((1)/(R_1)+(1)/(R_(2)))`

Answer

C