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प्रश्न
Explain the reason for glittering of diamond.
उत्तर
- The diamond appears dazzling because the total internal reflection of light happens inside the diamond.
- The refractive index of only diamonds is about 2.417. It is much larger than that for ordinary glass which is about only 1.5.
- The critical angle of a diamond is about 24.4°. It is much less than that of glass.
- A skilled diamond cutter makes use of this larger range of angle of incidence (24.4° to 90° inside the diamond), to ensure that light entering the diamond is total internally reflected from the many cut faces before getting out.
- This gives a sparkling effect for diamond.
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