Final answer:
When light passes from air to a denser medium like glass, the phenomenon that occurs is refraction.
Step-by-step explanation:
When light passes from air to a denser medium like glass, the phenomenon that occurs is refraction. Refraction is the bending of light as it passes from one medium to another with a different density. The change in density causes the light rays to change direction, resulting in the bending of the light.
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