What happens to a ray that is incident on a curved surface separating the two media ? Are the laws of refraction still valid ?

How do rays bend when they are incident on a curved surface ?

When monochormatic light is incident on a surface separating two media, the reflected the same frequency as the incident frequency. Explain why?

(a) When monochromatic light is incident on a surface separating two media, the reflected and refracted light both have the same frequency as the incident frequency. Explain why? (b) When light travels from a rarer to a denser medium, the speed decreases. Does the reduction in speed imply a reduction in the energy carried by the light wave? (c) In the wave picture of light, intensity of light is determined by the square of the amplitude of the wave. What determines the intensity of light in the photon picture of light

What happens to the light ray when a transparent material with two curved surfaces is placed in its path ?