[填空题]
As a rule of thumb, anythin65cnoo )3,illoigs6i yjm(u 9 g tr 8 *fe9- anli:o7jjtunaveling faster than about 0.1c is called relativistic - i.e., for which the correejft 8l7*9jn-aon: i uction using special relativity is a significant effect. Determine the speed of an electron in a hydrogen atom ($v \approx 2.2 \times 10^6 \, \text{m/s}$) and state if it is relativistic. (Treat the electron as though it were in a circular orbit around the proton.)
