E = hf what sort of Energy is this?

AI Thread Summary
The discussion centers on the relationship between energy expressed in the equation E = hf and its relevance to the equation E² = (mc²)² + (pc)². It clarifies that the energy (E) in E = hf pertains specifically to photons, which are massless particles. Participants confirm that this energy can indeed be related to the broader energy equation for particles, including those with mass. The conversation emphasizes the distinction between photon energy and the energy of massive particles. Understanding these relationships is crucial for grasping concepts in quantum mechanics and relativity.
WWCY
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Homework Statement


Is this E - say of an electron - the very E in E2 = (mc2)2 + (pc)2?

If it isn't, what sort of Energy is this?

Help is greatly appreciated!

Homework Equations

The Attempt at a Solution

 
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This is the E of a photon, a massless particle. So yes:
WWCY said:
the very E in E2 = (mc2)2 + (pc)2?
 

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