Question

A beam of light is a mixture of plane polarized and unpolarized light. When it is sent through a polaroid sheet, it is found that the transmitted intensity can be varied by a factor of 9 depending on the orientation of the polaroid. Find the relative intensities of the two components. A. 0.20 unpolarized, 0.80 plane polarized B. 0.25 unpolarized, 0.75 plane polarized C. 0.50 unpolarized, 0.50 plane polarized D. 0.60 unpolarized, 0.40 plane polarized E. 0.80 unpolarized, 0.20 plane polarized

Answer 1

Answer:

A. 0.20 unpolarized and 0.80 plane polarized.

Explanation:

After passing through polaroid sheet , unpolarised portion will get reduced by half . So this portion becomes .20/ 2 = 0.10

The polarized portion can face two situation depending upon the angle of the polaroid.

It may either be cut off to zero. So total intensity of transmitted light  wil be .10 + 0 = .10

It may or be passed fully . In that case total intensity of transmitted light will become 0 .10 +0.80 =0.90

Ratio of these two light of maximum and minimum intensity is 0.90 / 0.10 = 9.