`1000` small water drops, each of radius `r`, combine and form a big drop. In this process, find decrease in surface energy.

`1000` small water drops, each of radius `r`, combine and form a big d

1.	`1000` small water drops, each of radius `r`, combine and form a big drop. In this process, find decrease in surface energy.
Answer» Suppose radius of big drop is `R`. During this process, mass will be conserved, so volume will also be conserved. `("Volume")_("initial") = ("Volume")_("final")` `((4)/(3)pir^(3)) xx 1000 = ((4)/(3)piR^(3)) rArr R = 10r` loss in surface energy `DeltaU_("loss") = TDeltaA_("loss") = T((4pir^(2)) xx 1000 - 4pi(10r)^(2))` `DeltaU_("loss") = (T)(900 xx 4pir^(2))` this energy loss will be converted into heat. So increase in temperature of the drop can be found from `T(900 xx 4pir^(2)) = msDeltaT`, From this get the incerase in temperature `DeltaT`.

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`1000` small water drops, each of radius `r`, combine and form a big drop. In this process, find decrease in surface energy.

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