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Question
The total free surface energy of a liquid drop is `pisqrt2` times the surface tension of the liquid. Calculate the diameter of the drop in S.l. unit.
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Solution
Given: E = `pi sqrt2` T
To find: Diameter of drop (d)
Formula: E = TΔA
Calculation: ΔA = `4pir^2`
From formula,
E = `4pir^2`T
r = 0.5946 m
∴ d = 2r
= 2(0.5946)
∴ d = 1.1892 m
Diameter of the drop is 1.1892 m.
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