Solve the given question:
Question: 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 18.7 cm, and the voltage difference is 132 kV.
Part I: 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.)
Part II: What is the final velocity of the electron if you use relativistic mechanics?
If possible just a brief explanation how you got the answer?