A liquid drop of diameter D breaks up into 27 drops. Find the resultant change in energy.

Explanation

` (4)/(3) pi ((D)/(2))^3 = 27 xx (4pi )/(3) ((d)/(2)) ^3 rArr D = 3d ` Now change in surface energy `= T xx ` change in surface area
` rArr Delta U = T[n 4pi d ^ 2 - 4pi D^2 ], n= 27 rArr Delta U = 2pi D^2 T `