## Momentum

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

Marni Kahn 1A
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### Momentum

Why is momentum involved in the debrogile equation if the mass of a particle is so tiny and isn't that significant?

MingdaH 3B
Posts: 133
Joined: Thu Jul 11, 2019 12:17 am

### Re: Momentum

the mass is so small that the order of magnitude of the mass value significantly increases the wavelength, as it's in the denominator of de Broglie's equation. Without it, the equation wouldn't be at all accurate when compared to experimental data.

Abby Soriano 1J
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Joined: Sat Aug 24, 2019 12:16 am

### Re: Momentum

In the De Broglie Equation, λ = h/p, where h is Planck's constant (6.626 x 10^-34 J s) and p is the momentum (mass x velocity). Since h is already a very small number, the momentum of very small and high velocity objects (such as electrons) are significant because they calculate a wavelength that is long enough to be measured (and thus long enough to even matter). This is the exact opposite for large objects such as cars or baseballs since their wavelengths are so short that they are deemed insignificant.

Kassidy Ford 1I
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### Re: Momentum

As the person above said, a smaller particle with tiny masses will actually lead to a larger wavelength detected, because of their negligible mass. This is why large objects that have velocity, such as cars, do not act like waves, because their large masses lead to undetectably small wavelengths according to the debroglie equation

Rhea Shah 2F
Posts: 97
Joined: Thu Jul 25, 2019 12:17 am

### Re: Momentum

Momentum is involved in order to specify that the DeBroglie's equation is applicable only to particles with momentum. This specification is needed to make clear that the equation is not applicable to light particles as light does not have mass and therefore does not have momentum. Despite the almost negligible mass of electrons, it's still necessary to include their mass and velocity in the equation because wavelength properties are only noticed for particles with extremely small mass. Thus, wave properties are difficult to distinguish for large objects such as cars or baseballs.