question_answer 36)

                  The angle of contact at the interface of water glass is \[{{0}^{o}}\], Ethylalcohol-glass is \[{{0}^{o}}\], Mercury-glass is \[{{140}^{o}}\] and Methyliodide-glass is \[{{30}^{o}}\]. 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                 (a) water                             (b) ethylalocolol                 (c) mercutry                       (d) methyliodide                

Answer:

                  (c) When angle of acute is obtuse \[(>{{90}^{o}})\], meniscus is convex.