Assertion (A): A diamond sparkles more than a glass imitation cut to the same shape. Reason (R): The refractive index of diamond is less than that of glass. In the context of the above two statements, which one of the following is correct?
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- ABoth A and R are true, and R is the correct explanation of A
- BBoth A and R are true, but R is not a correct explanation of A
- CA is true, but R is falseCorrect
- DA is false, but R is true
Explanation
The correct option is C because Assertion A is true while Reason R is false.
A diamond sparkles more than glass because it has a very high refractive index, approximately 2.42, compared to glass which is around 1.5. This high refractive index results in a very small critical angle for diamond. When light enters a diamond, it undergoes multiple total internal reflections before exiting, which creates the intense sparkling effect.
Reason R is false because the refractive index of diamond is significantly higher, not less, than that of glass. For an imitation to sparkle like a real diamond, it would need a higher refractive index, not a lower one.
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