Two waves of same frequency and same amplitude from two monochromatic sources are allowed to superpose at a certain point. If in one case the phase difference is 0 and in other case it is `pi//2` then the ratio of the intensities in the two cases will be

Options

A. `1:1`
B. `2:1`
C. `4:1`
D. None of the above

Answer

B

Explanation

Where phase difference is 0, intensity is maximum
where, `phi=pi/2 or phi/2=pi/4`
the intensity will be `I=I_(max)"cos"^(2)phi/2=I_(max)/2`
`:.` The desired ratio is `2:1`