Question

In a double-slit experiment what will happen to the interference pattern shown on the screen if

a) the wavelength of the light is increased?

b) the distance between the slits is increased?

c) the screen is moved further away from the slits?

Answer 1

The fringe with will get affected in all of these cases mentioned above the fringe with of an interference pattern is directly proportional to the wavelength and distance between slits and screen and inversely proportional to distance between the two slits.

So

a) fringe width will increase so we will have broader maxima and minima regions

b) frige width will decrease so the interference pattern will become narrower maximum and minima regions

c) fringe width will increase the result will be same as a