find the difference in excess pressure on the inside and outside of a rain drop ,if its diameter changes from 1.003 cm to 1.002 cm by evaporation. surface tension of rain water is 72 dyne /cm

Dear student,

The excess pressure on inside and outside rain drop is given by $p=\frac{2T}{r}$
The excess pressure on inside and outside rain drop when diameter is 1.003 cm is p_{1
$p_1=\frac{2\times 72}{1.003}=143.56 dyne/c{m}^2$}
The excess pressure on inside and outside of rain drop when the diameter is 1.002 cm is p₂
$p_2=\frac{2\times 72}{1.002}=143.71 dyne/c{m}^2$
The difference in excess pressure of rain drop is 
$∆p=p_2-p_1=143.71-143.56 = 0.15 dyne/c{m}^2$

Regards.