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प्रश्न
Water rises to a height of 20 mm in a capillary tube. If the radius made 1/3rd of its previous value, to what height will the water now rise in the tube?
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उत्तर
As, `h_1/h_2 = r_2/r_1`
∴ h2 = `(h_1r_1)/r_2 = 20 xx r_1/((r_1"/"3)) = 60` mm
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