Assume that a drop of liquid evaporates by decreases 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 surface tension is T, density of liquid is `rho` and L is its latent heat of vaporization.

Answer

A

Explanation

Decreses in surface energy=heat required in vaporization.
`:. T(dS)=L(dm)`
`:. T(2)(4 pi r)dr=L(4 pi r^(2)dr)rho`
`:. r=(2T)/(rho L)`
The correct option is (d).