Question

Which among the following is not an example of tyndall effect?

• A. The visible beam of headlights in fog
• B. A beam of sunlight becomes visible as it passes through dust particles in the air of a room
• C. When sunlight passes through a canopy of a dense forest, tiny droplets in the mist scatter light
• D. Blue colour of the sky

Answer 1

The correct option is D Blue colour of the sky

The phenomenon of scattering of light by the colloidal particles gives rise to tyndall effect.
This phenomenon is seen when a fine beam of sunlight enters a dusty room through a small hole. Thus, the scattering of light makes the particles visible.
Tyndall effect can also be observed when sunlight passes through a canopy of a dense forest. Here, tiny water droplets in the mist scatter light.
Tyndall effect can also be observed when light from headlight passes through fog.
Blue colour of sky is due to scattering of light but this is not an example of tyndall effect.