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Grade 12th passAIPMT

a glass capilary tube of inner diameter .28mm is lowered verticaly in vessel find the pressure to be applied so that level owater both in vessel and tube is same

Profile image of apurva
8 Years agoGrade 12th pass
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1 Answer

Profile image of Eshan
8 Years ago
Dear student,

Due to formation of meniscus, the pressure inside water lowers and to balance it, water rises to some height.

The pressure applied to bring the water level in tube equal in height to that in the vessel, external pressure is needed to be applied
equal to that by which the formation of meniscus lowered it.

Hence required pressure= \dfrac{2T_{water}}{R} , T_{water}is the surface tension of water.