Question

1000 small water drops, each of radius r and charge q, coalesce to form a single big drop. The potential of big drop, how much times the small drop is:
(a) 1000
(b) 100
(c) 10
(d) 1

Answer 1

(b) 100
Vlarge = n2/3Vsmall
Vlarge = (103)2/3Vsmall
[∵ n = 1000, n = 103]
∴ Vlarge = 102Vsmall = 100Vsmall