Question 10****A proton with rest energy \(938\,\mathrm{MeV}\) moves at \(0.800c\). Find \(p\) in \(\mathrm{MeV}\,c^{-1}\).
Question 12****+A particle has \(pc=4.00\,\mathrm{GeV}\) and rest energy \(3.00\,\mathrm{GeV}\). Find its speed as a fraction of \(c\).
Question 19*****A particle and antiparticle have equal and opposite momenta. Explain why total momentum is zero but total energy is not.
Question 20*****Explain why relativistic momentum is needed for momentum conservation to hold in all inertial frames.