Re: Thomas Young's experiment

[Bernard Cleyet <anngeorg@PACBELL.NET>]

try replacing the card with a strip whose depth is the same as its width.

bc

Ludwik Kowalski wrote:

> Referring to Young's experiment I wrote last night:
>
> >. . . In my view it was a an experiment producing
> > diffraction by a single obstacle. The central fringe
> > was most likely two times wider than two
> > neighboring fringes.
>
> Today, after reading the original Young's paper,
> sent to me by Stephen, I became aware that this
> was wrong. Young was very specific about this.
> He wrote: "fringes have nearly equal width where
> light remains white." We know that in using white
> light fringes (others than m=0) are colored. So he
> was looking exactly where a two times wider (and
> much more intense) diffraction peak would appear.
> Young would certainly notice its double width.
>
> Apparently, the beam of light on each side of the
> slip card is acting as a single slit. But why was I
> wrong in thinking that the slip card would act as
> a single obstacle (like a wire)? I do not know.
> Ludwik Kowalski