Explain the phenomenon of capillarity . Derive an expression for the rice of liquid in a capillary tube
Answers
Answer:
The phenomenon of rise or fall of a liquid in a capillary tube is called capillarity. T=r(h+r3)ρg2cosθ. For capillary r3 can be neglected h=2Tcosθrρg . this is called Ascent formula.
Answer:
Capillarity is a physical phenomenon in which liquids flow without the help of gravity. Liquids even rise to a height against gravity, through narrow tubes. Capillary action is due to the phenomenon of Surface tension of liquid as well as adhesive forces between liquid molecules and molecules of the narrow tube.
W = ρ (πD²/4) h g --(1)
The surface on the top liquid inside the capillary tube has a trough (cup) like shape. Assume the angle of contact with the walls be Ф. Surface tension is the contact force per unit length along the circumference of top surface. This force pulls the liquid vertically upwards.