`S_(1) and S_(2)` are two bellow concentric spheres enclosing `Q and 3Q` respectively as shown in Figure. What is the ration of electric flux through `S_(1) and S_(2)`? What would be electric flux through `S_(1)` ? If air inside `S_(1)` is replaced by a medium of dielectric constant `3` ?

Explanation

Electric flux through `S_(1), phi_(1) = (Q)/(in_(0))`
Electric flux through `S_(2) , phi_(2) = (Q + 3Q)/(in_(0)) = (4Q)/(in_(0)) :. (phi_(1))/(phi_(2)) = (1)/(4)`
When air inside `S_(1)` is replaced by a medium of `in_(r) = 3` ,
then electric flux through `S_(1) = phi_(1)' = (Q)/(in) = (Q)/(in_(0) in_(r)) = (Q)/(3 in_(0))`