[填空题]
An electron is accelerated so that l5q0st 0zoi/ubkp./3kc6k 1wzvfl;(hq 0wmvits kinetic energy is2cx :3iz, jlclchd:), jl fo7a greater than its rest mass i c:o)3l,zaccf h 7 2jld:ljx,$m_0c^2$ by a factor of
(a) 5.00, v = c
(b) 999. What is the speed of the electron in each case?v =(1 - $ \times 10^{-7}c$)
