A drop of liquid of surface tension sigma and diameter D breaks up into 8 tiny drops. Calculate the resulting change in energy.

A drop of liquid of surface tension sigma and diameter D breaks up int

1.	A drop of liquid of surface tension sigma and diameter D breaks up into 8 tiny drops. Calculate the resulting change in energy.
Answer» Solution :Radius of bigger drop =D/2 Let radius of each small drop =r Volume of bigger drop= Volume of 8 smaller drops `rArr 4/3 PI (D/2)^(3)=8 xx 4/3 pi r^(3)` `rArr D/2=2r` Surface AREA of bigger drop `=4PI (D/2)^(2)` `=pi D^(2)` Surface area of 8 smaller drops `=8 xx 4pir^(2)` `=32 pi (D/4)^(2)` `=2pi D^(2)` Increase in surface area `=2pi D^(2)-pi D^(2)=pi D^(2)` Change in energy =Increase in surface area `xx" Surface tension"` `=pi D^(2) SIGMA`