Fluid Mechanics & Fluid Machines 8:- Capillary Action - Height of water in capillary tube, Rise in capillary

Fluid Mechanics & Fluid Machines

8. Capillary Action:- Height of water in capillary tube:- h = (4σ cos⁡θ)/ρgd where, h = Rise in capillary σ = surface tension of water & glass d = Diameter of tube θ = Angle of contact between the liquid and the material. θ = 0o for water and glass (clean) θ = 128o for mercury and glass (clean) When a liquid surface supports another liquid of density “ρ_b ". The rise in capillary is given as h = (4σ cos⁡θ)/((ρ-ρ_b)gd) Capillary action is due to adhesion and cohesion, both For capillary action diameter of tube should be less than 3cm.