Question

Why fringe width decreases with the increase in newton rings?

Answer 1

Answer:

One can say that rings are unequally spaced, because difference between two consecutive rings represents thickness of ring. In case of the wedge-shaped film, t remains constant along lines parallel to the thin edge of the wedge. Hence the maxima and minima are straight lines parallel to the thin edge of the wedge. If illuminated by white light, instead of dark and bright fringes, coloured fringes will be obtained.

please mark me brainlist