## Properties of photons

$c=\lambda v$

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### Properties of photons

How do photons have momentum but no mass? Not sure if I'm understanding the lecture properly

Malakai Espinosa 3E
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### Re: Properties of photons

Photons do have a mass! They're a little heavier than electrons. I didn't catch the part about photons not having mass in lecture, but photons, neutrons, and electrons all have mass. Hope that clarifies things.

Wait ignore this I misread the question.
Last edited by Malakai Espinosa 3E on Mon Oct 19, 2020 2:29 pm, edited 1 time in total.

Claire_Kim_2F
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### Re: Properties of photons

Your statement is correct and photons get their energy from their momentum rather from their mass because they still obey the equation E=pc.

Crystal Yu 1D
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### Re: Properties of photons

Photons do not have a rest mass, but they do have momentum. This is why the De Broglie equation still works for photons. I'm not sure exactly which part of the lecture you were referring to, but I hope this helps! :)

Malakai Espinosa 3E
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### Re: Properties of photons

Malakai Espinosa 3D wrote:Photons do have a mass! They're a little heavier than electrons. I didn't catch the part about photons not having mass in lecture, but photons, neutrons, and electrons all have mass. Hope that clarifies things.

Wait my bad I thought you were talking about protons haha. Like the others said, photons are particles of light so they don't have an actual mass but they still have momentum so they can still be used in equations concerning momentum like De Broglie.