Diamond’s Shine – Rankers Physics

Total Internal Reflection: Practice Problem & Solution

Assertion (A): Diamond in air shine brightly and when dipped in transparent oil, its shine reduces. Reason (R): Diamond shines due to multiple total internal reflections.  
Both (A) & (R) are true and the (R) is the correct explanation of the (A)
Both (A) & (R) are true but the (R) is not the correct explanation of the (A)
(A) is true but (R) is false
Both (A) and (R) are false

Solution Explained:

To solve this problem, we apply the core principles of Total Internal Reflection. Understanding the underlying formula is key to arriving at the correct answer below:

Diamond's high refractive index leads to a small critical angle, causing multiple total internal reflections (TIR) and bright shine. When in oil, the refractive index difference with the surroundings decreases, increasing the critical angle, reducing TIR, and thus reducing its shine. Both (A) and (R) are true, and (R) explains (A).

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Similar Practice Questions

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