Two Polaroids P 1 and P 2 are placed with their axis perpendicular to each other. Unpolarised light with intensity I 0 is incident on P 1 . A third polaroid P 3 is kept in between P 1 and P 2 such that its axis makes an angle 45 o with that of P 1 . The intensity of transmitted light through P 2 is

Question

Aicharya · Accepted Answer

By Malus law, the intensity of transmitted light via

P_{1}

is

I_{1} = \frac{I_{0}}{2}

The intensity of light transmitted through

P_{3}

as obtained from the above figure is

I_{2} = \frac{I_{0}}{2} \cos^{2} 45^{o}

= \frac{I_{0}}{2} \times \frac{1}{2}

= \frac{I_{0}}{4}

Intensity of light transmitted via

P_{2}

is

I_{3} = \frac{I_{0}}{4} \cos^{2} 45^{o}

I_{3} = \frac{I_{0}}{8}

Two Polaroids P 1 and P 2 are placed with their axis perpendicular to each other. Unpolarised light with…

Solution