A wetting liquid rises 3 cm in a capillary tube when the system is stationary. The apparatus is then accelerated vertically downward at 5 m/s². Take g = 10 m/s². If the new capillary rise is N cm, find N.
Physics · Properties of solid and fluid · properties of fluid and surface tension
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Question

A wetting liquid rises 3 cm in a capillary tube when the system is stationary. The apparatus is then accelerated vertically downward at 5 m/s². Take g = 10 m/s². If the new capillary rise is N cm, find N.

Physics · Properties of solid and fluid · properties of fluid and surface tension

G1 Physics · Accepted Answer

During downward acceleration, g(eff) = g−a = 10−5 = 5 m/s². Capillary height varies inversely with effective gravity. Therefore, h = h₀g/(g−a) = 3×10/5 = 6 cm. Hence, N = 6.