The refractive index of diamond is much greater than that of ordinary glass. Is this fact of some use to a diamond cutter? - Physics

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Short Note

The refractive index of diamond is much greater than that of ordinary glass. Is this fact of some use to a diamond cutter?

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Solution

Yes

The refractive index of diamond (2.42) is more than that of ordinary glass (1.5). The critical angle for diamond is less than that for glass. A diamond cutter uses a large angle of incidence to ensure that the light entering the diamond is totally reflected from its face. This is the reason for the sparkling effect of a diamond.

Concept: Refraction
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Chapter 9: Ray Optics and Optical Instruments - Exercise [Page 346]

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NCERT Physics Class 12
Chapter 9 Ray Optics and Optical Instruments
Exercise | Q 9.18 (e) | Page 346
NCERT Physics Class 12
Chapter 9 Ray Optics and Optical Instruments
Exercise | Q 18.5 | Page 347

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