A beam of unpolarised light of intensity
Question:

A beam of unpolarised light of intensity $\mathrm{I}_{0}$ is passed through a polaroid $\mathrm{A}$ and then through another polaroid $\mathrm{B}$ which is oriented so that its principal plane makes an angle of $45^{\circ}$ relative to that of $\mathrm{A}$. The intensity of the emergent light is :-

1.  $\mathrm{I}_{0}$

2. $\mathrm{I}_{0} / 2$

3. $\mathrm{I}_{0} / 4$

4. $\mathrm{I}_{0} / 8$

Correct Option: , 3

Solution: