What is the energy of a photon in relation to E=MC^2?

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SUMMARY

The energy of a photon cannot be calculated using the standard equation E=MC², as this equation applies only to particles with rest mass. Photons, which have zero rest mass, require the use of the more general equation E=√((m₀c²)² + (pc)²), where p represents momentum. For photons, energy is directly related to momentum, expressed as E=pc. This distinction is crucial for understanding the behavior of light in physics.

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E=MC^2 question about the "M"

So, energy equals mass times the speed of light squared.

Energy can determine speed, because the energy is transferred into the 3 spatial dimensions.

My question is with E=MC^2 itself, Energy of light would equal zero mass times the speed of light squared, right? But that would mean light had zero energy. Care to help explain? I really want to figure this out, and I'm reading the Elegant Universe right now so it would help to understand this before going in too much further.

Thanks,

-Lazer
 
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This question actually comes up a lot. [itex]E = m_{0}c^{2}[/itex] is only valid for particles in their rest frames (the [itex]m_{0}[/itex] is the rest mass). A photon has no rest frame so the equation does not apply to it. In general, [itex]E = \sqrt{(m_{0}c^{2})^{2} + (pc)^{2}}[/itex] so for a photon [itex]E = pc[/itex] where p is the momentum.
 

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