What occurs when light passes from air into glass?

When light passes from air into glass, it bends towards the normal line. This bending occurs because the speed of light changes as it moves from one medium to another. In air, light travels faster than it does in glass due to glass being a denser material.

When light enters glass, its speed decreases, causing the light rays to change direction towards the normal — an imaginary line that is perpendicular to the surface at the point of entry. As a result, the angle of refraction (the angle between the refracted light and the normal) is smaller than the angle of incidence (the angle between the incident light and the normal). This phenomenon can be explained by Snell's Law, which describes how light refracts when transitioning between mediums of different densities.

The other options do not correctly describe what happens during this transition, as light does not bend away from the normal when entering a denser medium like glass, nor does it travel in the same direction or stop at the boundary. Understanding this behavior is essential for grasping concepts related to optics and light behavior in various materials.