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Human Eye and Colourful World — Science STD 10 — Question

CBSE BoardEnglish MediumSTD 10ScienceHuman Eye and Colourful World3 Marks
Question
Why is Tyndall effect shown by colloidal particles? State four instances of observing the Tyndall effect.
✓

Answer

Colloidal particle show Tyndall effect as they scatter light. Small sized colloidal particles cannot be seen with naked eyes but they are big enough to scatter a beam of light.
  • When a fine beam of light enters a smoke-filled dark room through a small hole.
  • When sunlight passes through a canopy of dense forest in foggy/ misty conditions.
  • Blue colour of sky.
  • Red colour of the sun during sunrise or sunset.

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