- #36

bob012345

Gold Member

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In any collision having multiple particles each will have a different ##\gamma## factor if they have different velocities and any transformation to another reference frame will involve yet another ##\gamma## factor. It seems to me the simplest answer to the OP question is that it is always and only the total

Also, I disagree that the concept of relativistic mass is a bad idea. It seems very natural and is the reason for the difference in Newtonian momentum and relativistic momentum. In both cases we can write ##\vec p = m \vec v## but understand in the Newtonian case ##m## is the intrinsic rest mass ##m_o## and in the relativistic case it is ##m = \gamma m_o##

*relativistic*momentum and energy that are conserved but in the low velocity limit all the ##\gamma## factors approach 1. It would be more instructive to do a relativistic momentum conservation problem properly and then see how it looks Newtonian in the limit as ##\large \frac{v}{c}## is very small.Also, I disagree that the concept of relativistic mass is a bad idea. It seems very natural and is the reason for the difference in Newtonian momentum and relativistic momentum. In both cases we can write ##\vec p = m \vec v## but understand in the Newtonian case ##m## is the intrinsic rest mass ##m_o## and in the relativistic case it is ##m = \gamma m_o##

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