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Question
The rise of a liquid in a capillary tube depends on
(a) the material
(b) the length
(c) the outer radius
(d) the inner radius of the tube
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Solution
\[\text{ Height of the liquid in the capillary tube is given by }: \]
\[\text{ h } = \frac{2Scos\theta}{r\rho g}\]
\[\text{ h = Height }\]
\[\text{ S = Surface tension }\]
\[\text{ r = Inner radius of the tube }\]
\[\rho = \text{ Density of the liquid }\]
\[\text{ g = Acceleration due to gravity }\]
\[a) \theta \text{ and } \rho \text{ depend upon the material of the capillary tube and the liquid }. \]
\[b) \text{ h is dependent on the length of the tube . If the length is insufficient, then h will be low } . \]
\[d) \text{ r is the inner radius of the tube } .\]
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