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Question
A certain number of spherical drops of a liquid of radius R coalesce to form a single drop of radius R and volume V. If T is the surface tension of the liquid, then
Options
energy = `4 "VT" (1/"r" - 1/"R")` is released
energy = `3 "VT" (1/"r" + 1/"R")` is absorbed
energy = `3 "VT" (1/"r" - 1/"R")` is released
energy is neither released nor absorbed
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Solution
energy = `3 "VT" (1/"r" - 1/"R")` is released
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