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Question
The contact angle between pure water and pure silver is 90°. If a capillary tube made of silver is dipped at one end in pure water, will the water rise in the capillary?
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Solution
No, the water will neither rise nor fall in the silver capillary.
\[\text{ According to Jurin's law, the level of water inside a capillary tube is given by }\]
\[h = \frac{2Tcos\theta}{r\rho g}\]
\[\text{ Here }, \theta = {90}^0 \]
\[ \Rightarrow h = \frac{2Tcos {90}^0}{r\rho g} \]
\[ \Rightarrow h = 0\]
Thus, the water level neither rises nor falls.
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