An electron is accelerated inside a parallel plate capacitor. The electron leaves the negative plate with a negligible initial velocity and then after the acceleration it hits the positive plate with a final velocity ?. The distance between the plates is 12.3 cm, and the voltage difference is 131 kV. Determine the final velocity ? of the electron using classical mechanics. (The rest mass of the electron is 9.11×10-31 kg, the rest energy of the electron is 511 keV.)
What is the final velocity of the electron if you use relativistic mechanics?