Chapter 9 · Physics
Regular vs Diffused Reflection
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A mirror and a white wall both reflect light; only the mirror shows your face. Smooth surfaces keep rays parallel; rough ones scatter them.
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PDF, 170 KB · fill in the blanks, true/false, assertion-reason, MCQ, numericals, short answer, match the columns; detailed solutions at the end Up next in this chapter
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Key points
- Smooth surface → parallel rays stay parallel → image: regular reflection.
- Rough surface → rays scatter → no image: diffused reflection.
- Each ray still obeys i = r at its own tiny facet.
- Diffused reflection lets us see a book from any angle; a wet road becomes smoother and glares.
Smooth vs rough
| Feature | Regular | Diffused |
|---|---|---|
| Surface | Smooth | Rough |
| Reflected rays | Parallel | Scattered |
| Image | Forms | Does not form |
| Laws of reflection | Obeyed | Obeyed at every facet |
Try it yourself
Goal: See how surface roughness turns regular reflection into diffused reflection.
- Start with the slider at 0% (smooth).
- Increase the roughness and watch the reflected rays spread.
- Check the readout: every ray still has i = r.
Quick quiz
4 questions. Choose an answer for each, then submit to see your score and the explanations.
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