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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?
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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