Total Internal Reflection and Snell’s Law – Rankers Physics

Total Internal Reflection: Practice Problem & Solution

Assertion (A): When light moves from a denser medium to rarer medium then Snell's law can't satisfied for all angle of incidence. Reason (R): When light moves from denser to rarer medium, for angle of incidence greater than the critical angle, no refraction is possible.  
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:

Total internal reflection occurs when light travels from a denser to a rarer medium, and the angle of incidence (theta_i) is greater than the critical angle (theta_c). In this case, (sintheta_r) from Snell's law becomes greater than 1, implying no refraction is possible. Thus, Snell's law is not satisfied for all incidence angles, and the reason correctly explains this phenomenon.

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