In Young's experiment ratio of maximum and minimum intensities of fringes is 9: 1. Ratio of amplitude of superposing waves = .....

Options

A. `9:1`
B. `3:1`
C. `2:1`
D. `1:1`

Answer

C

Explanation

`(I_(max))/(I_(min))= :.(9)/(1)=((E_(1)+E_(2))/(E_(1)-E_(2)))^(2)`
`:. (E_(1)+E_(2))/(E_(1)-E_(2))=(3)/(1) [ :.` Taking square root]
Now, Taking componendo- dividendo,
`(2E_(1))/(2E_(2))=(3+1)/(3-1) :. (E_(1))/(E_(2))=(2)/(1) =2:1`