SKEDSOFT

Physics For Engineers - 1

  Upon rearranging,

                   

Where,              

(The eqn. reduces to single slit expression if b=0,d=2d).

The intensity at point P is therefore,

                  where

The maximum intensity at point is

               

Which is 4 times the intensity due to individual slit and appears at the point on screen midway between the slits.