Here's why:
* Index of Refraction: The index of refraction (n) is a measure of how much light slows down when it passes from one medium to another. It's the ratio of the speed of light in a vacuum to the speed of light in the medium.
* Acrylic vs. Air: Acrylic has a relatively constant index of refraction (around 1.49), while air has a very low index of refraction (approximately 1.00).
* Snell's Law: The relationship between the angles of incidence and refraction is governed by Snell's Law: n₁sinθ₁ = n₂sinθ₂. This law shows that the ratio of the indices of refraction (n₁/n₂) is directly related to the ratio of the sines of the angles of incidence and refraction.
Therefore, when light travels from air into acrylic, the ratio of their indices of refraction remains nearly constant, causing the light to bend at a predictable angle.
