Q79. a screen has two slits, each of width w with their centres at a distance 2w apart. ft is illuminated by a monochromatic plane wave travelling along the x -

Q79. A screen has two slits, each of width w with their centres at a distance 2w apart. ft is illuminated by a monochromatic plane wave travelling along the x -axis. The intensity of the interference pattern, measured on a distant screen, at an angle 0=*to the x-axis is (a) zero for n = 1,2,3... b) maximum for n =1,2,3... (C) maximum for n =S. (d) zero for n=0 only w W