Ratio of intensities of two waves is 9:1. If these two are superimposed, what is the ratio of maximum and minimum intensities?

Options

A. `4 : 1`
B. `3 : 1`
C. `2 : 1`
D. `1 : 1`

Answer

A

Explanation

`(I_(1))/(I_(2))=((A_(1))/(A_(2)))^(2)=(9)/(1)rArr(A_(1))/(A_(2))=(3)/(1)`
`:. (I_(max))/(I_(min))=((A_(1)+A_(2))/(A_(1)-A_(2)))^(2)=((A_(1)/(A_(2))+1)/((A_(1))/(A_(2))-1))^(2)=((3+1)/(3-1))^(2)=((4)/(2))^(2)=4:1`.