Question

When an unpolarized light of intensity, $I_o$ is incident on a polarizing sheet, the intensity of light which does not get transmitted is :

• A. $\frac{I_o}{2}$
• B. $\frac{I_o}{4}$
• C. zero
• D. $I_o$

Answer 1

The correct option is A $\frac{I_o}{2}$

A Polarizing sheet transmits only the component of light polarized along a particular direction and absorbs the component perpendicular to that direction.
Consider a light beam in the z direction incident on a Polaroid which has its transmission axis in the y direction. On the average, half of the incident light has its polarization axis in the y direction and half in the x direction. Thus half the intensity is transmitted,and the transmitted light is linearly polarized in the y direction.