Question

Find the ratio of intensities at two points x and y on a 'screen in Young's double slit experiment, where waves from S₁ and S₂ have path difference of (i) 0 and (ii) λ/4 .
(Ans. : 2 : 1)

Answer 1

Hey mate
what is the position of these points

Answer 2

Explanation:

Let I0 be the frequency of either of the interfering sources, where d is the phase difference between the two disturbances at p, the intensity I at a point P.

d = 0; I = 4Io cos²0 -- 1

= 4I(1)² = 4I

Let I0 be the frequency of either of the interfering sources, where d is the phase difference at p between the two disturbances, the intensity I at a point Q.

d = 90°; I = 4Iocos²(45°) -- 2

Dividing 1 by 2 we will get -

= 2:1