How Does Light Intensity Vary with One Slit in a Diffraction Experiment?

[Vaseline]

If one slit is used instead of 2 in a diffraction experiment, how does light intensity vary?

I think.. Central fringe brighter, symmetrical fringes either side of central fringe, central maximum twice the width of side fringes..

But I'm not sure why?

Also, using diffraction gratings – why is the maximum brightness in the middle?

 

[diazona]

Think about why fringes exist at all when you have 2 slits. Does the same reasoning apply with 1 slit?

 

[nlightner]

I can provide some insights into the light slit experiment and the variation in light intensity. In a diffraction experiment, when only one slit is used instead of two, the light intensity will vary in a distinct pattern. The central fringe will appear brighter than the symmetrical fringes on either side. This is because the central fringe is the result of constructive interference, where the waves from the single slit overlap and amplify each other, resulting in a higher intensity.

The symmetrical fringes on either side of the central fringe are the result of destructive interference, where the waves from the single slit cancel each other out, resulting in lower intensity. The central maximum will also be twice the width of the side fringes because the central fringe is the result of two overlapping waves, while the side fringes are the result of only one wave.

As for the reason why the maximum brightness is in the middle when using diffraction gratings, it is because diffraction gratings have multiple slits that are very close together. This results in a larger number of overlapping waves, leading to a stronger central maximum and a more pronounced pattern of fringes. Additionally, the spacing between the slits in a diffraction grating is carefully designed to maximize the constructive interference in the central maximum.

In summary, the variation in light intensity in a light slit experiment can be explained by the principles of constructive and destructive interference. And the maximum brightness in the middle when using diffraction gratings is due to the multiple, closely spaced slits that result in a stronger central maximum. I hope this helps to clarify your understanding of the experiment.