As shown in the figure, three identical polaroids P_1, P_2 and P_3 are placed one after another. The pass axis of P_2 and P_3 are inclined at angle…

As shown in the figure, three identical polaroids $\displaystyle \mathrm{P}_1, \mathrm{P}_2$ and $\displaystyle \mathrm{P}_3$ are placed one after another. The pass axis of $\displaystyle \mathrm{P}_2$ and $\displaystyle \mathrm{P}_3$ are inclined at angle of $\displaystyle 60^{\circ}$ and $\displaystyle 90^{\circ}$ with respect to axis of $\displaystyle \mathrm{P}_1$. The source S has an intensity of $\displaystyle 256 \frac{\mathrm{~W}}{\mathrm{~m}^2}$. The intensity of light at point O is $\displaystyle \_\_\_\_$ $\displaystyle \frac{W}{m^2}$.