The ray diagrams given below show the paths of a ray of light travelling from a medium M into different media 1,2 and 3.
(a) In which of three media 1,2 or 3 does light travel: (i) faster, (ii) slower than in medium M?
(b) Arrange the media L, 2 and 3 in descending order of (i) speed of light through them, (ii) their refractive index.
