Question

A drop of mercury of radius $2mm$ is split into 8 identical droplets. Find the increase in surface energy. (Surface tension of mercury is $0.465{J/m}^2$)

• A. $23.4\mu J$
• B. $18.5\mu J$
• C. $26.8\mu J$
• D. $16.8\mu J$

Answer 1

The correct option is A $23.4\mu J$

As we know,

Increase in surface energy or work is done in splitting a big drop

$=4\pi R^{2}T(n^{1/3}-1)$

$\Rightarrow W=4\pi \ast (2\ast {10}^{-3}{)}^2\ast 0.465(8^{1/3}-1)=23.4\mu J$