The electron momentum is E/c, so that its speed is....

AI Thread Summary
The discussion revolves around a physics homework problem concerning the momentum of an electron, with references to key equations such as E = γmc² and p = γmv. The original poster is struggling to complete the final part of the question and is advised to include their attempted solution for clarity, as per forum guidelines. It is emphasized that the context of the question is crucial, as energy divided by c pertains to massless particles, not electrons. Participants stress the importance of showing work to identify errors and facilitate assistance. Overall, the thread highlights the need for context and adherence to forum rules in academic discussions.
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Homework Statement


upload_2017-12-24_11-47-57.png

Homework Equations


E = γmc2
p = γmv
K = E - mc2
E2 = c2p2 + m2c4

The Attempt at a Solution


I have completed most of this question, but I am struggling to get the required result to the final part of the question.[/B]
 

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Please note that forum guidelines require you to show your attempted solution. Without it, how are we supposed to see where you have gone wrong?

Also, please include (and preferably type out) the entire question. It seems to me that what you have given is a part of a larger question. Taken out of context, the question makes no sense since the energy divided by c is only the momentum for a massless particle, which the electron is not.
 
Orodruin said:
Please note that forum guidelines require you to show your attempted solution. Without it, how are we supposed to see where you have gone wrong?

Also, please include (and preferably type out) the entire question. It seems to me that what you have given is a part of a larger question. Taken out of context, the question makes no sense since the energy divided by c is only the momentum for a massless particle, which the electron is not.

I've posted the rest of the question. My attempts at this part of the question are lots of messy algebraic manipulations. I'd just like to know the correct way to approach the problem.
 
The forum rules require you to provide your attempt. It is not optional Nobody here is going to reply unless you do since that would also break forum rules.
 
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