Question

When refraction phenomenon occurs, then?

Answer 1

Answer:

Refraction occurs when light goes through a water surface since water has a refractive index of 1.33 and air has a refractive index of about 1. Looking at a straight object, such as a pencil in the figure here, which is placed at a slant, partially in the water, the object appears to bend at the water's surface

Answer 2

Refraction occurs as light passes from one medium to another only when there is a difference in the index of refraction between the two materials.

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