Here, we have to find out the shape of the liquid meniscus in a capillary tube dipped in mercury.
We have, If the adhesive force is greater than the cohesive force, the shape of the meniscus will be concave. If cohesive force is greater than adhesive force, the shape of the meniscus will be convex. Ordinary liquids like water show capillary rise and the liquid meniscus is concave upwards. Mercury shows capillary depression and the liquid meniscus is convex upwards. For mercury, the cohesive force is more than the adhesive force.