What is Tyndall effect? What is its cause ? Name two phenomena observed in daily life based on Tyndall effect.

Explanation

Tyndal cffect: When a beam of light is passed through a colloidal solution placed in a dark room the path of beam becomes illuminated when observed through a microscope placed perpcndicular to the path of light. This effect is called Tyndall effect.
Causes of tyndal effeet: The size of the callidal partical is relatively larger then the solute particals ofa true solution. The collidal particles first absorb energy from the incident light and then a part of energy from their surface. Thus tyndall effect is due to scattering of light by the colloidal particals and the colloidal particles are seen to be moving as points of lights moving aginist a dark background.
Daily life examples :
(i) When sunlight passcs though a canopy of a dense forest the tiny water droplets in the mist scatter light and become visible.
(ii) When a fine beam of sunlight entersa smoke filled room through a small hole the smoke particals become visible due to the scattcring of light.