Twenty-seven identical liquid drops, each of radius 2 mm, coalesce completely into one spherical drop. If the final radius is N mm, find N.

Question

G1 Physics · Accepted Answer

By volume conservation, R = r∛n. Here, n = 27, ∛27 = 3, r = 2 mm. Therefore, R = 2×3 = 6 mm. Hence, N = 6.