## Wave Properties of electrons

$c=\lambda v$

April Meza 3K
Posts: 66
Joined: Sat Sep 21, 2019 12:36 am

### Wave Properties of electrons

In the wave of properties of electrons Lecture diffraction was mentioned. Dr. Lavelle mentioned that light waves in general show diffraction patterns. I am confused as to what exactly diffraction patterns are. Can someone please explain? Thanks!

Nare Arakelian Dis 3E
Posts: 58
Joined: Thu Jul 11, 2019 12:16 am

### Re: Wave Properties of electrons

When waves encounter a barrier, like a wall, with small slits or openings, the waves will spread out past the openings and create these patterns as they interfere with one another. This is my understanding, I hope it helped!

Ariana Iranmahboub1G
Posts: 114
Joined: Fri Aug 09, 2019 12:17 am

### Re: Wave Properties of electrons

Diffraction patterns according the textbook are "the pattern of high and low intensities generated by an object in the path of a ray of light". Diffraction patterns are formed by constructive interference, in which the peaks coincide (waves are in phase), and destructive interference, in which one peak of the wave coincides with the trough of the other wave (waves are out of phase).

Maeve Miller 1A
Posts: 51
Joined: Fri Aug 09, 2019 12:16 am

### Re: Wave Properties of electrons

Diffraction, at least in my experience, is something more discussed in physics, but it refers to the spreading of light as it passes through a narrow space--like we were discussing during the photoelectric effect lecture. The pattern of light particles he drew on the board after having passed through the NaCl was the diffraction pattern.

Sanjana Borle 2K
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Joined: Fri Aug 09, 2019 12:15 am

### Re: Wave Properties of electrons

Diffraction is basically when the light passes through a small slit/opening and causes different kinds of patterns. These patterns involve constructive or destructive interference. In constructive interference the amplitudes of two(or more) waves "add up" causing the amplitude to increase and the intensity of the light to increase. In destructive interference the opposite happens: waves "cancel out" each other's amplitudes, making the total intensity smaller, zero, or even negative.

cassidysong 1K
Posts: 100
Joined: Fri Aug 30, 2019 12:15 am

### Re: Wave Properties of electrons

Diffraction patterns are how light spreads out when it passes through a small passage. Based on the diffraction patterns there must be waves in phase (constructive) and waves out of phase (destructive interference) where the waves either line up with each other or they don't and they can cancel each other out if they're the same amplitude.

Frederick Keith_4C
Posts: 65
Joined: Thu Sep 26, 2019 12:19 am

### Re: Wave Properties of electrons

Diffraction is basically just the bending of waves around an obstacle or through a slit. I think everyone has already covered the topics of constructive and destructive interference fairly well, so to further elaborate on the topic, I'll just provide some examples of diffraction.
Ex 1) the spaced tracks on a CD act as diffraction gratings which is why we see the rainbow color on the CD (light wave)
Ex 2) you can still hear someone call your name even if they are talking behind a tree or pole (sound wave)
Ex 3) Ocean waves diffract around piers and buoys and other obstacles
Remember diffraction can occur with any type of wave; its not just light, although it is the most apparent and easy to observe with light.

Fdonovan 3D
Posts: 101
Joined: Sat Aug 17, 2019 12:16 am

### Re: Wave Properties of electrons

Diffraction is what sets light (and other things that travel in waves, ie. sound) apart from particles. Light is able to bend around obstacles and in doing so certain diffraction patterns emerge. The way the pattern is arranged depends on how the light spreads around an object.