Two identical drops of coalesce to form a bigger drop. Find the ratio of the surface energy of a bigger drop to a smaller drop.
Step 1: Given data
Two identical drops of coalesce to form a bigger drop
Step 2: Formula used
Volume,
=surface energy, =surface tension, = surface area
Step 3: Find the relation between the radius of bigger and smaller drop
Let two drops of radii combines together to form a drop of radii .
Therefore,
Step 4: Calculate the ratio of surface tensions of both drops
Now surface energy = surface tension surface area
Ratio of surface energy for the bigger and smaller drop:
, As tension is same in both cases and surface area ,
Hence, the ratio of the surface energy of bigger drop to smaller drop becomes,
Hence, option A is correct.