Answer:
Explanation:
This problem indicates that the speed of light in a material medium is 0.5 10⁸ m / s, they ask to find the critical angle between the material and the vacuum
Let's find the refractive index of the material
n = c / v
n = 3 10⁸ / 0.5 10⁸
n = 6
When the material passes from one medium to another, it must comply with the law of refraction
n₁ sin θ = n₂ sin θ₂
for the angle criticize the angles tea2 = 90
tea = sin⁻¹n₂/ n₁
The vacuum replacement index is n₂ = 1
tea = sin⁻¹ (1/6)
tea = 9.59º