Assume that a drop of liquid evaporates by decrease in its surface energy, so that its temperature remains unchanged. What should be the minimum radius of the drop for this to be possible ? The surfrace tension is T, density of liquid is p and L is its latent heat of vaporization.

Assume that a drop of liquid evaporates by decrease in its surface ene

1.	Assume that a drop of liquid evaporates by decrease in its surface energy, so that its temperature remains unchanged. What should be the minimum radius of the drop for this to be possible ? The surfrace tension is T, density of liquid is p and L is its latent heat of vaporization.
Answer» `sqrt(T//PL)` `T//pL` `2T//pL` `pL//T` Solution :`p4piR^(2)DeltaRL=T4pi[R^(2)-(R-DeltaR)^(2)]` `PR^(2)DeltaRL=T[R^(2)-R^(2)+2RDeltaR-DeltaR^(2)]` `pR^(2)DeltaRL=T2RDeltaR`(`DeltaR` is very small) `R=(2T)/(pL)` So, correct . choice is ( c)

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Assume that a drop of liquid evaporates by decrease in its surface energy, so that its temperature remains unchanged. What should be the minimum radius of the drop for this to be possible ? The surfrace tension is T, density of liquid is p and L is its latent heat of vaporization.

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