A point source S emitting light of wavelength 600 nm is placed at a very small height h above flat reflecting surface AB (see figure). The intensity of the reflected light is 36% of the incident intensity. Interference fringes are observed on a screen placed parallel to the reflecting surface at a very large distance D from it.
(a) What is the shape of the interference fringes on the screen ?
(b) Calculated the ratio of the minimum to the maximum intensities in the interference fringes formed near the point P (shown in the figure)
(c) if the intensity at point P corresponds to a maximum, calculated the minimum distance through which the reflecting surface AB should be shifted so that the intensity at P again becomes maximum.
