Same chapter3 marksDifficulty: Medium
Distinguish between interference and diffraction of light.
Wave Optics
3 marksDifficulty: Medium
State Huygens' principle and use it to explain refraction qualitatively.
Original Khojo Papers practice question — not from a past board paper.
Answer
Every point on a wavefront acts as a source of secondary wavelets that spread out in all directions with the speed of the wave, and the new wavefront is the surface tangent to all of them. When a wavefront enters a denser medium obliquely, the part that enters first slows down, so the wavefront turns towards the normal, which is refraction.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
The same construction gives the laws of reflection.
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