Let n number of little droplets of water of surface tension S (dyne/cm), all of the same radius r cm combine to from a single drop of radius R heat, while using cgs system of units answer the following questions. If the radius of the big drop formed is made two times without any change in temperature then the work done isA. `4 pi R^(2) S`B. `8 pi R^(2) S`C. `12 pi R^(2) S`D. `16 pi R^(2) S`

Let n number of little droplets of water of surface tension S (dyne/cm

1.	Let n number of little droplets of water of surface tension S (dyne/cm), all of the same radius r cm combine to from a single drop of radius R heat, while using cgs system of units answer the following questions. If the radius of the big drop formed is made two times without any change in temperature then the work done isA. `4 pi R^(2) S`B. `8 pi R^(2) S`C. `12 pi R^(2) S`D. `16 pi R^(2) S`
Answer» Correct Answer - C Work done = S.T. x change in surface area `=S[4 pi(2 R)^(2) - 4pi R^(2)]` `=Sxx12 pi R^(2)`

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