Final answer:
The medium with the lowest index of refraction, which is substance 'a' with n=1.33, will yield the largest angle of refraction when monochromatic light with a certain angle of incidence enters it. The answer is option a.
Step-by-step explanation:
The student is asking which medium will lead to the largest refracted angle when monochromatic light with a certain angle of incidence (θ) passes from air into various substances with different indices of refraction (n). According to Snell's Law, the angle of refraction is inversely proportional to the material's index of refraction when light enters from air into the material. The substances provided are:
- a. n=1.33
- b. n=1.5
- c. n=1.47
- d. n=2.4
Snell's Law states that n₁ * sin(θ₁) = n₂ * sin(θ₂), where n₁ is the index of refraction of the first medium (air in this case, with n=1), θ₁ is the angle of incidence, n₂ is the index of refraction of the second medium, and θ₂ is the refracted angle. To find the medium with the largest angle of refraction, we look for the lowest index of refraction since the medium with the lowest n₂ value will result in the largest sin(θ₂), thereby giving the largest θ₂. In the options provided, medium 'a' with n=1.33 has the lowest index of refraction, thus, it will have the largest angle of refraction for a given angle of incidence.
Hence, the answer is option a.