what is capillary fall
Answers
Answer:
Capillary is a phenomenon of rising or falling of liquid surface in a small tube compared to the adjacent normal liquid level.
Answer:
A capillary tube is a tube with a very fine bore. The phenomenon of a rise and fall of a liquid inside a capillary tube when it is dipped in the liquid is called capillary action or capillarity. When a glass capillary is immersed in water, the water rises inside the tube. When a glass tube is immersed in mercury, the level of mercury inside the tube falls below the level in the outer vessel.
Examples of capillarity: Blotting paper absorbs ink or water, ink rises in a pen, oil rises in wicks of a lamp.
When chalk piece is immersed in water, bubbles are emitted:
Chalk is porous in nature. In these pores, the air is trapped. When chalk piece is dropped in water, due to capillary action water enters the pores of the chalk. Due to which the trapped air comes out of the pores in the form of bubbles.
Everyday Examples of Capillarity:
Due to capillary action oil rises through wicks of lamps.
Due to capillary action water rises through the sap of trees.
Due to capillary action ink is absorbed by blotting paper.
Due to capillary action liquids are absorbed by sponges.
Bricks and mortar, which are porous, permit the rise of soil water through them by capillary action. To avoid it, the base is made using damp-proof cement.
Soil water rises to the surface by capillary action and evaporates. To conserve soil water, the farmers plough their fields in summer. The loosening of the top layer of the soil breaks up the fine capillaries through which the deeper down water is sucked up. Thus the loss of water in the soil is prevented.
Due to depression in the level of mercury in a capillary tube, a correction is to be applied for mercury barometer.