In a Young's double slit experiment, the light sources is at distance `l_1 = 20mu m ` and `l_2 = 40 mu m` form the main slit. The light of wavelength lambda = 500nm is incident on slits separated at a distance `10mu m `. A screen is placed at a distance D = 2 away from the slits as shown in figure. Find
(a) the values of `theta` relative to the central line where maxima appear on the screen?
(b) how many maxima will appear on the screen?
(c) what should be the minimum thickness of a slab of refractive index 1.5 placed on the path of one of the ray so that minima occurs at C ?
` .

Answer

`[(a) sin^(-1)[2((n)/(40)-1)];(b)40; (c ) 5000Å]`