`n` charged drops, each of radius `r` and charge `q`, coalesce to from a big drop of radius `R` and charge `Q`. If `V` is the electric potential and `E` is the electric field at the surface of a drop, then.

Explanation

For each small drop, `V_(1) = (q)/(4pi in_(0) r)`
When n small drops coalesce to from oen big drop of radius R, then as
`(4)/(3) pi R^(3) = n xx (4)/(3) pi r^(3), :. R = n^(1//3) r`
Total charge Q = nq
`:.` Potential of big drop,
`V_(b) = (Q)/(4pi in_(0) R) = (nq)/(4pi in_(0) m^(1//3) r)`
`V_(b) = n^(2//3) V`,