Using the concept of rise due to surface tension,
r2T=hρg
T=2rhρg=215×10−5×15×10−2×900×10=101milliNewtonm−1
When a long glass capillary tube of radius 0.015cm is dipped in a liquid, the liquid rises to a height of 15cm within it. If the contact angle between the liquid and glass to close to 0∘, the surface tension of the liquid, in milliNewton m−1, is [ρ(liqued) =900kgm−3,g=10ms−2] (Given answer in closed integer)
Held on 3 Sept 2020 · Verified 6 Jul 2026.
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