If the critical angle for a certain material is 45°, what is the refractive inde
Practice Questions
Q1
If the critical angle for a certain material is 45°, what is the refractive index of that material?
1.41
1.00
1.73
0.71
Questions & Step-by-Step Solutions
If the critical angle for a certain material is 45°, what is the refractive index of that material?
Correct Answer: 1.41
Step 1: Understand that the critical angle (θc) is the angle of incidence above which total internal reflection occurs.
Step 2: Know the formula to find the refractive index (n) using the critical angle: n = 1/sin(θc).
Step 3: Substitute the given critical angle (θc = 45°) into the formula: n = 1/sin(45°).
Step 4: Calculate sin(45°). The value of sin(45°) is approximately 0.7071.
Step 5: Now, substitute this value back into the formula: n = 1/0.7071.
Step 6: Perform the division: n ≈ 1.41.
Critical Angle and Refractive Index – The critical angle is the angle of incidence above which total internal reflection occurs, and it is related to the refractive index of a material through the formula n = 1/sin(θc).
