Final answer:
When someone walks into water, their feet appear separated from their legs due to the refraction of light.
Step-by-step explanation:
When a person walks into the water, their feet appear separated from their legs because of the phenomenon called refraction of light. Refraction occurs when light waves bend as they pass from one medium (in this case, air) to another medium (water). The bending of light causes an apparent shift in the position of objects, resulting in the observed separation of the feet and legs in water.
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