HSC Science (Computer Science) 12th Board ExamMaharashtra State Board
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Find the Height to Which the Same Water Will Rise in Another Glass Capillary Having Half Area of Cross Section. - HSC Science (Computer Science) 12th Board Exam - Physics

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

The surface tension of water placed in a capillary is given in terms of height of the water column, angle of contact between water and glass which is 0°, radius of the capillary tube, density of the water, and the acceleration due to gravity as follows,

T = hρgr/2cosθ

the question says that the radius of the tube is decreased to 1/2 of the original value. Therefore the surface tension becomes

T' = h'ρg(r/2)/2cosθ

on comparing both equations we get,

hρgr/2cosθ = h'ρg(r/2)/2cosθ

∴ hr = h'r/2

∴ h = h'/2

∴ h' = 2h

∴ h' = 2 × 3.2

∴ h' = 6.4cm

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APPEARS IN

2013-2014 (October) (with solutions)
Question 2.7 | 2.00 marks

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Solution Find the Height to Which the Same Water Will Rise in Another Glass Capillary Having Half Area of Cross Section. Concept: Surface Tension.
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