In the figure (a) light is incident at an angle θ which is slightly greater than the critical angle. Now, keeping the incident fixed a slab of refractive index n₃ (n₃ < n₂) is placed on surface AB in fig. (b). Which of the following statements are correct :

Question

G1 Physics · Accepted Answer

Derived solution: Step 1: Apply Snell’s law n₁sin i = n₂sin r. For total internal reflection the ray must go from denser to rarer medium and sin C = n₂/n₁. Step 2: Test each statement independently using these relations and the data/figure. Step 3: The statements that satisfy the required optical conditions are A: total internal reflection occurs at AB for n₃ < n₁; C: the ray will return back to the same medium for all values of n₃. Hence the correct answer is A,C.

In the figure (a) light is incident at an angle θ which is slightly greater than the critical angle. Now, keeping the incident fixed a slab of refractive index n₃ (n₃ &lt; n₂) is placed on surface AB in fig. (b). Which of the following statements are correct :

In the figure (a) light is incident at an angle θ which is slightly greater than the critical angle. Now, keeping the incident fixed a slab of refractive index n₃ (n₃ < n₂) is placed on surface AB in fig. (b). Which of the following statements are correct :