Question

Which of the following statements is correct for the Tyndall effect?
A. Scattering and polarised of light by small suspended particles is called the Tyndall effect
B. Tyndall effect of colloidal particles is due to dispersion of light
C. Tyndall effect is due to the refraction of light
D. Tyndall effect is the zig-zag motion of suspended particles

Answer 1

Hint: Tyndall effect is the phenomenon where a scattering of light is observed. The colloidal particles are solid particles with a range of ~10nm distributed in a fluid medium.

Complete Step by Step Solution:
The Tyndall effect is named after an Irish physicist named John Tyndall.
Tyndall effect is explained as a phenomenon where on the dispersion of light or passing the beam of light through a medium containing colloidal particles, scattering of light is observed.
The strength of the scattered light is dependent on the colloidal particles' density and the incident light frequency.

When we pass a beam of light to the liquid medium containing colloidal particles, it collides with the particles as the light does not completely pass through the medium. This results in the deviation of light from its path. Due to the scattering of light by the colloidal particles, the path from which the beam of light passes becomes visible.

An example of Tyndall effects is the scattering of light by milk as it contains globules which are colloidal particles of fats and proteins.
Therefore, the Tyndall effect of colloidal particles is due to the dispersion of light. Hence, option B is correct.

Note: The diameter of colloidal particles which cause scattering of light can vary from 40-900nm.