## De Brogile's equation [ENDORSED]

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

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### De Brogile's equation

Can someone explain what Lavelle meant when he said not to use the equation for a photon for questions related to light?

Komal Prakash 1H
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### Re: De Brogile's equation  [ENDORSED]

We cannot use the De Brogile's equation for light, because wavelength=h/momentum, and momentum equals mass times velocity. Since photons do not have a mass, momentum would be zero, and we cannot divide by zero.

Vienna Cimetta 1L
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### Re: De Brogile's equation

The equation can only be used for something that has a rest mass. A photon of light does not, and therefore the equation cannot be used.

juliaschreib1A
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### Re: De Brogile's equation

Why do photons not have mass?? doesn't every existing thing have mass?

Chem_Mod
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### Re: De Brogile's equation

Photon is quantized electromagnetic radiation. It is a specific amount of energy and thus it does not have mass.