Question

what does tyndall effect mean actually

Answer 1

it means scattering of light as a beam light passes through a colloid..

Answer 2

Tyndall effect
The Tyndall Effect is the effect of light scattering in colloidal dispersion, while showing no light in a true solution. This effect is used to determine whether a mixture is a true solution or a colloid.

For example, light being shined through water and milk. The light is not reflected when passing through the water because it is not a colloid. It is however reflected in all directions when it passes through the milk, which is colloidal.

A second example is shining a flashlight into fog or smog; the beam of light can be easily seen because the fog is a colloid.

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