## Deriving the DeBrogile Equation

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

305086803
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Joined: Wed Sep 18, 2019 12:16 am

### Deriving the DeBrogile Equation

Hi Everyone,

I know that Dr. Lavelle goes super in-depth when deriving equations, such as the DeBrogile, and I'm assuming he does so that we can get a better understanding of what it does. I was wondering how important it was for us to 100% know how to derive the equation. Is it fine if we have the basic understanding of what it does?

Thanks

KeyaV1C
Posts: 103
Joined: Sat Aug 17, 2019 12:17 am
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### Re: Deriving the DeBrogile Equation

It’s probably a good idea to remember how to derive it especially since it’s a pretty short derivation. λ=h/p and p=mv so λ=h/mv

Ruby Tang 2J
Posts: 102
Joined: Fri Aug 30, 2019 12:15 am

### Re: Deriving the DeBrogile Equation

It is probably fine that you have a basic understanding of what it does, but I guess the main takeaway in deriving the DeBroglie Equation is that you can combine E=pc and E=hv to get hc/λ = pc --> h/λ = p --> h/λ = mv --> λ = h/mv

Ruth Glauber 1C
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Joined: Wed Sep 18, 2019 12:20 am

### Re: Deriving the DeBrogile Equation

I think it's useful to know how to derive it!

Ian Morris 3C
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Joined: Wed Sep 18, 2019 12:18 am

### Re: Deriving the DeBrogile Equation

Usually it is useful to be able to derive a simpler equation like this, as the derivation can be helpful for a question of a test.

Petrina Kan 2I
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Joined: Fri Aug 30, 2019 12:17 am

### Re: Deriving the DeBrogile Equation

While I think it's not totally necessary to memorize and know the derivation, it might prove to be helpful since the equations used to derive it are equations that we should know and memorize anyways! This way we can have a greater knowledge of how these concepts work together which could hopefully help on a test. :)

Sean1F
Posts: 19
Joined: Sat Sep 07, 2019 12:16 am

### Re: Deriving the DeBrogile Equation

Petrina Kan 3C wrote:While I think it's not totally necessary to memorize and know the derivation, it might prove to be helpful since the equations used to derive it are equations that we should know and memorize anyways! This way we can have a greater knowledge of how these concepts work together which could hopefully help on a test. :)

I agree! What's important is that you know the equations and how to use them. I find it similar to calculus where you need to know equations and methods of finding answers but not really where they come from.

DMuth_1J
Posts: 63
Joined: Thu Jul 11, 2019 12:15 am

### Re: Deriving the DeBrogile Equation

It would also be helpful to know how to derive the equation because you can use the base equations as opposed to the complete, derived one.

Lauren Lewis3L
Posts: 57
Joined: Wed Feb 20, 2019 12:16 am

### Re: Deriving the DeBrogile Equation

Are we going to get the Planck's constant number or do we have to memorize it?