If the spacing between the slits d is very large, what happens to the spacing between the zero intensity points?

Question

Which of these makes sense? (only pick 1)

It would become very small.

It would depend on other details of the experimental setup.

It would not change.

It would become equal to the slit spacing d.

It would become very large.

Answer 1

Hi Uswah T.,

The thing to remember about single and double slits, is that they have similar dependencies on the lateral details of the slit/slits. So you can remember what a double slit does, based on what a single slit does. And you can remember what a single slit does, based on your very own observation. Go outside at night, and sight a distant very bright light source (such as a vapor streetlight). It should be both bright, and distant (hence, appear small). Look at it through a slit made by squeezing together two of your fingers on the same hand, held up near your face (brace your hand against your forehead). With just a little bit of effort, you will be able to generate a single slit pattern, yourself, and see what happens as you squeeze it down to nothing wide, then what happens as you open it back up. After you have done this, you will never forget it!

--Cheers, _- Mr. d.