011220 | Wave Optics

Light from sodium lamp (S) passes through two polaroid sheets P1 and P2 as shown in fig. What will be the effect on the intensity of light transmitted (i) by P1 and (ii) by P2 on rotating polaroid P1 about the direction of propagation of light? Justify your answer in both cases.

OR

Define the term 'wave front of light'. A plane wave front AB propagating from denser medium (1) into a rarer medium (2) is incident on the surface P1P2 separating the two media as shown in fig. 

Using Huygen's principle, draw the secondary wavelets and obtain the refracted wave front in the diagram.
[2020 | Delhi | Section - B | SET - 1 SET - 2 SET - 3, Q.27 Q.22 Q.25]