# Light intensity through 2 slits

Nihalum

## Homework Statement

Monochromatic light of wavelength 620nm is going through a very narrow gap through the first curtain,then encounters a second curtain that is parallel with the first in which there are two parallel narrow slits S1 and S2 as shown in Fig. Slit S1 is located at the point of the second curtain that is closest point S, and S2 is d away from the S1. At point P, which is equidistant from the S1 and S2 we measure the intensity of the light and get the same intensity in both cases when only one of the leaked S1 and S2 is open, while in the case when both are open, we get 3 times greater the intensity. Determine the minimum distance d of slits, when the slits S and S1 are at distance L = 12dm.

## Homework Equations

path/vave length=phase difference/2*pi

The intensity is proportional to the electric wave squared

## The Attempt at a Solution

I tried to solve this using phasors, but in the end I am left with the equation containing the unknown term of phase difference (which contains the distance between the slits) and the intensity of a single slit. Am I doing it right?