A small sphere of radius `r_(1)` and charge `q_(1)` is enclosed by a spherical shell of radius `r_(2)` and charge `q_(2)`. Show that if `q_(1)` is positive, charge will necessarily flow from the sphere to the shell (when the two are connected by a wire) no matter what the charge `q_(2)` on the shell is [Fig]

Explanation

Hint: By Gauss’s law, field between the sphere and the shell is determined by `q_(1)` alone. Hence, potential difference between the sphere and the shell is independent of `q_(2)`. If `q_(1)` is positive, this potential difference is always positive.