A small liquid drop of radius $R$ is divided into 27 identical liquid drops. If the surface tension is $T$, then the work done in the process will be:
Solution
<p>Volume constant</p>
<p>$$\begin{aligned}
& \frac{4}{3} \pi R^3=27 \times \frac{4}{3} \times \pi r^3 \\
& R^3=27 r^3 \\
& R=3 r \\
& r=\frac{R}{3} \\
& r^2=\frac{R^2}{9}
\end{aligned}$$</p>
<p>$$\begin{aligned}
& \text { Work done }=T . \Delta A \\
& =27 T\left(4 \pi r^2\right)-T 4 \pi R^2 \\
& =27 T 4 \pi \frac{R^2}{9}-4 \pi R^2 T \\
& =8 \pi R^2 T
\end{aligned}$$</p>
About this question
Subject: Physics · Chapter: Properties of Solids and Liquids · Topic: Elasticity
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