JEE Mains · Physics · STD 11 - 9.2 surface tension
A big drop is formed by coalescing \(1000\) small identical drops of water. If \(E_1\) be the total surface energy of \(1000\) small drops of water and \(E_2\) be the surface energy of single big drop of water, the \(E_1\) : \(\mathrm{E}_2\) is \(\mathrm{x}: 1\) where \(x\) = _____.
- A \(9\)
- B \(10\)
- C \(11\)
- D \(12\)
Answer & Solution
Correct Answer
(B) \(10\)
Step-by-step Solution
Detailed explanation
\(\rho\left({ }_3^4 \pi r^3\right) 1000={ }_3^4 \pi R^3 \rho\) \(R=10 r\) \(E_1=1000 \times 4 \pi r^2 \times S\) \(E_2=4 \pi(10 r)^2 S\) \(\frac{E_1}{E_2}=\frac{10}{1}, x=10\)
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