일반물리학 2 — Relativity: Problem 9

9 The mass of an electron is \( 9.109\ 381\ 88 \times 10^{-31}\text{ kg} \). To six significant figures, find (a) \( \gamma \) and (b) \( \beta \) for an electron with kinetic energy \( K = 300.000\text{ MeV} \).