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Question
Which of the following graphs may represent the relation between the capillary rise hand the radius r of the capillary?
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Solution
\[\text{ The relationship between height h and radius r is given by: } \]
\[\text{ h } = \frac{2Scos\theta}{r\rho g}\]
\[\text{ If S, }\theta, \rho \text{ and g are considered constant, we have:} \]
\[\text{ h } \propto \frac{1}{r}\]
This equation has the characteristic of a rectangular hyperbola. Therefore, curve (c) is a rectangular hyperbola.
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