Question

The path of a light beam in air goes from an angle of incidence of 35° to an angle of refraction of 22° when it enters a rectangular block of plastic. What is the index of refraction of the plastic?

a. 1.53
b. 0.65

Answer 1

Using Snell's Law with the given angle of incidence (35°) and angle of refraction (22°), and knowing the index of refraction of air, we can calculate that the index of refraction for the plastic is approximately 1.53.

Step-by-step explanation:

To find the index of refraction of the plastic, we can use Snell's Law which is given by n₁sin(θ₁) = n₂sin(θ₂), where n₁ is the index of refraction of the first medium, θ₁ is the angle of incidence, n₂ is the index of refraction of the second medium, and θ₂ is the angle of refraction. Given that the light is moving from air into plastic, n₁ for air is approximately 1.00. We are provided with the angle of incidence of 35° and the angle of refraction of 22°. Applying Snell's Law: 1.00 * sin(35°) = n₂ * sin(22°). Solving for n₂ gives us the index of refraction of the plastic.

Using the sine values for these angles, we calculate: sin(35°) ≈ 0.5736 and sin(22°) ≈ 0.3746. Therefore, n₂ = 1.00 * 0.5736 / 0.3746 ≈ 1.53. Hence, the index of refraction of the plastic is approximately 1.53.