Question

(A) What is meant by scattering of light? How do our observations differ when white light (sun light) is scattered from (i) very fine particles of the medium and (ii) very large particles of the medium?

OR

(B) With the help of a ray diagram, explain a phenomenon of formation of spectrum in nature.

Accepted Answer

Scattering is light redirection by medium particles. Fine particles scatter short blue wavelengths; large particles scatter all wavelengths equally producing white light.. (A) **Scattering of Light:** The phenomenon in which light is deflected in various directions by tiny particles/molecules in a medium. (i) **Very fine particles:** Scatter light of shorter wavelengths mainly (blue end of the spectrum), making the sky appear blue. (ii) **Very large particles:** Scatter all wavelengths almost equally, so the scattered light appears white (e.g., clouds appear white). **(B) Rainbow Formation:** - Natural spectrum formed due to dispersion of sunlight by water droplets. - Sunlight entering a raindrop first undergoes **refraction and dispersion**, splitting into component colors. - Then it undergoes **total internal reflection** inside the drop, and finally **refraction** again when exiting the drop.

Scattering of Light and Spectrum

Explanation

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