The bending of a light wave as it slows down after hitting a medium is called refraction.

Here's a breakdown:

* Refraction is the change in direction of a light wave as it passes from one medium to another. This change in direction is caused by the change in speed of light as it travels through different mediums.

* Medium refers to the substance through which light travels, such as air, water, or glass.

* Speed of light is different in different mediums. Light travels fastest in a vacuum, and slower in denser mediums like water or glass.

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