The angle of contact at the interface of water glass is `0^(@)` ethylalcohol-glass is `0^(@)` mercury glas is `140^(@)` and methyliodide-glass is `30^(@)` A glass capillary is put in a through containing one of these four liquids. It is observed that the meniscus is convex. The liquid in the through is

Options

A. water
B. ethylalcohol
C. mercury
D. methyliodide

Answer

C

Explanation

`tanalpha=(F_(c)sin135^(@))/(F_(alpha)+F_(c)cos135^(@))=(F_(c))/(sqrt(2)F_(alpha)-F_(c))`