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Question
Water rises to a height 3.2 cm in a glass capillary tube. Find the height to which the same water will rise in another glass capillary having half area of cross section.
Solution
`h_1` = 3.2cm, `A_2 = (A_1)/2`
As, `h α 1/r`
`therefore h_1r_1 = h_2r_2`
`pir_2^2 = (pir_1^2)/2`
`=> r_2 = (r_1)/sqrt2`
`therefore h_2 = (3.2 xx r_1)/(r_1//sqrt2) = 3.2 xx sqrt2`
Hence, `h_2 = 4.525` cm
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