K.C.S.E Physics Q & A - MODEL 2016PP1QN04

K.C.S.E Physics Q & A - MODEL 2016PP1QN04

​Figure 2(a) and 2(b) shows capillary tubes inserted in water and mercury respectively.

​It is observed that in water the meniscus in the capillary tube is higher than the meniscus in the beaker, while in the mercury the meniscus in the capillary tube is lower than the meniscus in the beaker. Explain this observation 

answer

• In (a), the adhesive force between water and capillary tube is stronger than the cohesive force between the water molecules while in (b) the cohesive forces between mercury and the tube is higher than the adhesive force between mercury and the tube.