A sphere `S_(1)` of radius `r_(1)` encloses a net charge Q. If there is another concentric sphere `S_(2)` of radius `r_(2)(r_(2)gtr_(1))` enclosing charge `2Q` , find the ratio of the electric flux through `S_(1)andS_(2)` . How will the electric flux through sphere `S_(1)` change, if a medium of dielectric constant K is introduced in the space inside `S_(2)` in place of air ?

Explanation

Flux through `S_(1)phi_(1)(Q)/(epsilon_(0))`
Flux through `S_(2),phi_(2)=(Q+2Q)/(epsilon_(0))=(3Q)/(epsilon_(0))`
Ratio of flux `=1:3`
No change in the flux through `S_(1)` with dielectric medium inside the sphere `S_(2)`.