Question
A mercury drop of radius 1.0 mm breaks up into 64 droplets of equal volumes. Calculate the work done in this process. (Surface tension is mercury is 0.465 N/m)

None of these



diffcult
Solution
Let R be the radius of the drop and r the radius of each droplet.
Volume of one big drop = volume of 64 droplets.
.
.
Increase in surfacearea is
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work done W = surface tension increase in surface area
.
.
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