Question

define :angle of emergence

Answer 1

The angle of emergence is the angle of the light coming out of a medium (for an example a glass slab with parallel sides). The first medium could be air and the medium in the middle could be water or a glass slab with parallel sides. The ray of light travels down at an angle through the air and enters the glass.

Answer 2

Angle of emergence is the angle between the emergent ray and the normal (at the point of emergence) to the surface from which it is emerging after refraction.

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