College Physics 10th Edition by Raymond Serway,Chris Vuille

Exercise 20

(a) Show that a potential difference of 1.02 × 10 6 V would be sufficient to give an electron a speed equal to twice the speed of light if Newtonian mechanics remained valid at high speeds. (b) What speed would an electron actually acquire in falling through a potential difference equal to 1.02 × 10 6 V