# Optimum gap size for diffraction

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1. Oct 22, 2015

### The_Nster

1. The problem statement, all variables and given/known data

Is diffraction at a maximum when the width of the gap is similar in length to the wavelength of the light? (ie. W ≈ λ, where w=width)

Or is it a maximum when the width is smaller than the wavelength? (i.e W < λ)

Thanks for the help!

2. Relevant equations

n/a (this is a homework problem, but it is more theory based, so I have no work or equations)
3. The attempt at a solution
n/a

2. Oct 22, 2015

### Simon Bridge

What do you mean by "diffraction at a maximum"? How would you quantify the amount of diffraction?
By width, do you mean the separation of the slits or the width of the slits?
What level is this question posed at?

Usually students are taught an approximation of the diffraction maths which works well when the gap (multi-slit) is of the order of the wavelength of the light.

3. Oct 22, 2015

### The_Nster

Hi Simon, thanks for the reply!

By width, I mean the width of the slit opening (I am referring to single slit diffraction).

As for maximum diffraction, I see how that is not a great way to phrase it. Ignore 'maximum', so instead of "which would cause maximum diffraction", substitute "which would cause the most diffraction".

So you are saying that the most diffraction would occur when the width of the slit is in the same order of magnitude as the wavelength?, so would it then be right to say that less diffraction would occur if the wavelength is multiple orders of magnitude larger than the slit?

thanks for the help again!

4. Oct 22, 2015

### Simon Bridge

In that case, same question with the new words.
How do you quantify the amount of diffraction soas to determine what is the most?

If the slit was almost zero width, what would the diffraction pattern look like?
What sort of diffraction work have you done so far? Any math? Any practical?

5. Oct 23, 2015

### The_Nster

Hi Simon, thanks for replying again, I really appreciate your help!

I am doing high school level physics (so it should be pretty basic - no complicated math, or experimentation, it is just purely conceptual), and as for 'most' diffraction, look at the image here http://www.imagen-estilo.com/images/Newsimages/diffract.jpg ,where the image in the top left corner represents a 'small amount' of diffraction, and the image in the top right hand corner represents 'larger' diffraction (ignore the bottom image).

I have not done any diffraction work so far, just miscellaneous questions from my textbook (but none of them specifically address this issue)

Hopefully that makes it clearer.

Thanks again for your time and help!

6. Oct 23, 2015

### Simon Bridge

So what is itvabout the pics that tells you there is "more diffraction" in one than in the other?
Im not asking for my benifit, but to get you to think more scientifically.