Question

Mathematically prove that emergent ray is parallel to the incident ray.

Answer 1

Hey mate

By using snell's law of refraction we can prove it.

n21 = Sin i/Sin r

n21 = 1/n12

n12 = Sin r/Sin e

n21 = sin e / sinr

sin i / sinr = sin e/ sin r

thus , Sin i = Sin e

therefore , Incident ray is parallel to emergent ray

Hence proved