Two beams of light of intensity `l_(1) and l_(2)` interfere to given an interference pattern. If ratio of maximum intensity to that of minimum intersity is `25/9,` then `(l_(1))/(l_(2))` is

Options

A. `5/3`
B. 4
C. `81/625`
D. 16

Answer

D

Explanation

`(l_(max))/(l_(min))=29/9`
or `((a_(1)+a_(2))/(a_(1)-a_(2)))^(2)=25/9`
where, a denotes amplitude.
or `(a_(1)+a_(2))/(a_(1)-a_(2))=5/3`
or `(a_(1))/(a_(2))=4`
As, `("amplitude")^(2)prop` internsity
Hence, `(l_(1))/(l_(2))=((a_(1))/(a_(b)))^(2)=16`