Relativistic Energy and Velocity

AI Thread Summary
A proton with a mass of 938 MeV/c² is analyzed for its speed, momentum, and total energy given a kinetic energy of 1760 MeV. The confusion arises regarding the relevance of the 1760 MeV figure, initially thought to be total energy but later identified as kinetic energy. By assuming the kinetic energy as 1760 MeV, the calculations for speed, momentum, and total energy can proceed correctly. The discussion highlights the importance of correctly interpreting the energy values in relativistic physics problems. The solution ultimately confirms that the assumption was valid and led to the correct calculations.
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Homework Statement


A proton has a mass of 938 MeV/c2. Calculate the speed, momentum, and total energy of a 1760 MeV proton.

Homework Equations


E= mc^2 (Rest Energy)
E= Ɣmc^2 (Total Energy)
p= Ɣmv (momentum)
KE= mc^2(Ɣ-1) (Kinetic Energy)

The Attempt at a Solution


I'm not sure how the last number given (1760 MeV) is relevant, as in, I don't know what to do with it in order to start solving the problem. I know it isn't rest energy/mass because that is given as 938 MeV/c^2. It also is not the total energy because that is asked for in the question and the answer is not 1760 MeV.
 
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Normally I would think they meant the total energy, but perhaps they meant the kinetic energy. Try assuming the kinetic energy is 1760 MeV and see what you get.
 
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Lucas SV said:
Normally I would think they meant the total energy, but perhaps they meant the kinetic energy. Try assuming the kinetic energy is 1760 MeV and see what you get.
You're right. that worked. Thank you!
 
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