If you do an experiment on earth, and then do an identical experiment in a jet plane moving uniformly at a high speed, you get identical results from both experiments. This is an example of __________.
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Question 2
The mass of an electron and its antiparticle, a positron, is 0.511 MeV/c2 . In order to produce an electron-positron pair, a gamma ray must have an energy larger than 1.022 MeV because __________.
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