Question

a ray of light passes through the 4 transparent medias with refractive index n1,n2,n3,n4.the surface of all the medias are parallel. if the emergent ray CD is parallel to the incident ray AB we must have.....

Answer 1

According to Snell's law,

μsinθ=constant

Since the emergent ray is parallel to the incident ,the emergent angle = incident angle

Which gives, μ1=μ4

Mark it as brainliest