Question

A water drop when pressed between two parallel glass plates spreads in to a circle of diameter 10 cm. If the surface tension of water is $70\times10^{-3}Nm^{-1}$ and the force required to separate the two glass plates is 2.2 N, then the volume of the drop is nearly}

• A. $5\times10^{-4}m^{3}$
• B. $3.93\times10^{-6}m^{3}$
• C. $62.8\times10^{-6}m^{3}$
• D. $2\times10^{-6}m^{3}$ \bigskip

Hint:

Surface tension problems often reduce to force balance at edges.

Answer 1

The Correct Option is C