As a rule of thumb, anything traveling faster than about
Chapter 7, Problem 50GP(choose chapter or problem)
Problem 50GP
As a rule of thumb, anything traveling faster than about 0.1c is called relativistic—i.e., for which the correction using special relativity is a significant effect. Determine the speed of an electron in a hydrogen atom (radius 0.5 × 10−10 m) and state if it is relativistic. (Treat the electron as though it were in a circular orbit around the proton.)
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