JEE Mains · Physics · STD 11 - 9.2 surface tension
A small liquid drop of radius \(R\) is divided into \(27\) identical liquid drops. If the surface tension is \(\mathrm{T}\), then the work done in the process will be _______.
- A \(8 \pi R^2 \mathrm{~T}\)
- B \(3 \pi R^2 T\)
- C \(\frac{1}{8} \pi R^2 T\)
- D \(4 \pi R^2 \mathrm{~T}\)
Answer & Solution
Correct Answer
(A) \(8 \pi R^2 \mathrm{~T}\)
Step-by-step Solution
Detailed explanation
Volume constant \( \frac{4}{3} \pi \mathrm{R}^3=27 \times \frac{4}{3} \times \pi \mathrm{r}^3 \) \( \mathrm{R}^3=27 \mathrm{r}^3 \) \( \mathrm{R}=3 \mathrm{r} \) \( \mathrm{r}=\frac{\mathrm{R}}{3} \) \( \mathrm{r}^2=\frac{\mathrm{R}^2}{9}\) Work done…
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