Final answer:
Refraction occurs when a ray of light passes from one medium to another, resulting in a change in direction. An example is when a straw appears bent at the water's surface.
Step-by-step explanation:
When a ray of light passes from one medium to another, it changes direction. This phenomenon is called refraction. The ray of light is bent at the interface between the two media, and the bent ray is called the refracted ray.
An example of refraction can be observed when a straw is partially submerged in a glass of water. The straw appears to be bent at the water’s surface due to the refraction of light.
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