## Momentum of Photon

$c=\lambda v$

BenJohnson1H
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### Momentum of Photon

How can the momentum of a photon be calculated when a photon is essentially massless?

Chem_Mod
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### Re: Momentum of Photon

No objects are massless, so by using m x v one can determine momentums.

Sarah Zhao 4C
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### Re: Momentum of Photon

Mass of a photon is on the constants/equations sheet!

Brian Hom 2F
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### Re: Momentum of Photon

In classical electromagnetic theory, light turns out to have energy (E) and momentum (p), and these happen to be related by E = pc. Quantum mechanics introduces the idea that light can be viewed as a collection of "particles": photons. Even though these photons cannot be brought to rest, and so the idea of rest mass doesn't really apply to them, we can certainly bring these "particles" of light into the fold of equation by just considering them to have no rest mass.

Yukta Italia 3I
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### Re: Momentum of Photon

What are some examples of particles or objects that don't have any momentum? Is that even possible?