# diffraction

This forum made possible through the generous support of SDN members, donors, and sponsors. Thank you.

#### dudewheresmymd

##### Slowly Drifting...
10+ Year Member
TBR p.265-266 Physics II states: "When the opening is much larger than the wavelength, the wave doesn't distort much; when the opening is smaller than the wavelength or is of comparable size, the wave spreads out noticeably...The general relation is this: diffraction is more significant when the wavelength is smaller than or comparable to the opening the wave crosses; diffraction is less significant (or neglible) when the wavelength is much smaller than the opening."

I am confused by the bolded parts of this statement. Are the bolded parts saying the same thing? If so, it's a bit unclear to me. Could someone please reconcile these two in relation to figure 10-23 on page 265 or just explain diffraction in more understandable lay person terms?

Thanks!

TBR p.265-266 Physics II states: "When the opening is much larger than the wavelength, the wave doesn't distort much; when the opening is smaller than the wavelength or is of comparable size, the wave spreads out noticeably...The general relation is this: diffraction is more significant when the wavelength is smaller larger than or comparable to the opening the wave crosses; diffraction is less significant (or neglible) when the wavelength is much smaller than the opening."

I am confused by the bolded parts of this statement. Are the bolded parts saying the same thing? If so, it's a bit unclear to me. Could someone please reconcile these two in relation to figure 10-23 on page 265 or just explain diffraction in more understandable lay person terms?

Thanks!

That's a typo. There used to be some errata for TBR but I can't remember where.

Seems that strike does not work. Oh well, you get the idea.

Oh ok. So which is the right explanation?

The corrected one in red. Small/large is comparing the wavelength to the width of the slit. For wide slits, nothing exciting happens - easily observed through you window. As the width of the list starts getting closer to the wavelength, you'll observe more and more noticeable diffraction effects, eventually getting to the point where the slit becomes another point source of the wave.

Members don't see this ad :)
Excellent. Thanks man. Figure 10-23 finally makes sense now!

Excellent. Thanks man. Figure 10-23 finally makes sense now!

Your inbox is full and that's preventing you from understanding dispersion.

Ok it shouldn't be full anymore