Two waves having the intensities in the ratio of `9 : 1` produce interference. The ratio of maximum to minimum intensity is equal to

Options

A. `2:1`
B. `4:1`
C. `9:1`
D. `10:8`

Answer

B

Explanation

As intensity of wave `prop (amplitude)^2`
`I_1/I_2=9/1=a_1^2/a_1^2 implies a_1/a_2=3/1`
`I_(max)/I_(min)= (a_1+a_2)^2/(a_1-a_2)^2=16/4 implies ` ratio is `4:1`