Question

What is relation among radius of capillary(), radius of curvature(R) of meniscus and angle of contact (C)?​

Answer 1

Answer:

When a capillary tube is dipped in water, the water meniscus inside the tube is concave. The pressure just below the meniscus is less than the pressure just above it by 2T/R, where T is the surface tension of water and R is the radius of curvature of meniscus. The pressure on the surface of water is atmospheric pressure P. The pressure just below the plane surface of water outside the tube is also P, but that just below the meniscus inside the tube is P−(2T/R). We know that the pressure at all points in the same level of water must be the same. Therefore, to make up the deficiency of pressure, 2T/R, below meniscus, water begins to flow from outside to inside the tube. The rising of water in the capillary takes place.

Explanation: