$\lambda=\frac{h}{p}$

Talia Dini - 3I
Posts: 127
Joined: Wed Sep 30, 2020 9:32 pm

When classical particles (e.g., marbles, billiard balls, etc.,) hit a barrier with two or more holes do the particles that pass through the holes give rise to an observed diffraction pattern?

I'm having trouble understanding this question, can someone please explain it to me?

Lucy Wang 2J
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### Re: Question about post-module assessment

hey! could you be more specific about where this problem is from?

Breanna Ouyang 1I
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Joined: Wed Sep 30, 2020 9:48 pm

### Re: Question about post-module assessment

So those classical objects are particles, and the module discusses how electrons, in the referenced experiment, act as waves and not as particles. Particles would pass through the holes in the barrier, while waves would not pass through the barrier, but would interact with each other, constructively and destructively, to form a unique diffraction pattern. Particles would just either be stopped by the barrier or pass through the holes and be detected on the other side of the barrier since they do not act as waves.

Lorraine Jiang 2C
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### Re: Question about post-module assessment

Nope, they will not. This is because their sizes are too big for them to have diffraction patterns. On the other hand, electrons, or photons, are small enough so that they will have diffraction patterns. I think professor Lavelle mentioned this before, that whether a diffraction pattern will occur is related to the size of the particle.

Hope it helps!

Mackenzie Stockton 2H
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Joined: Wed Sep 30, 2020 10:11 pm

### Re: Question about post-module assessment

This is correct. Every day objects do not demonstrate diffraction patterns because their masses are large, so the value of their wavelength from the equation wavelength=h/momentum yields an extremely small wavelength. Because their wavelengths are so extremely small, we cannot measure/notice wavelike properties in everyday objects like the billard balls or marbles.

Zach Richardson 2f
Posts: 68
Joined: Wed Sep 30, 2020 9:32 pm

### Re: Question about post-module assessment

Everyday objects do not have wave properties and thus do not have diffraction patterns.