A beam of light passing from one transparent medium to another obliquely, undergoes an abrupt change in direction. This phenomenon is known as refraction of light.
1. Name the law which satisfies during this refraction.
2. Draw a figure, which shows refraction through a parallel sided glass slab (Ray passing from air)
3. Using the figure obtained in (b), show that the incident ray and the emergent ray are parallel to each other. Redraw the same figure, if the light is entering from a medium denser than glass. Justify your answer.