An electron of mass 9.11 × 10−³¹ kg moves with a speed of 0.800c.What is its total energy? (c = 3.00 × 10⁸ m/s)

Question

Quizplus · Accepted Answer

The total energy (E) of the electron is given by the relativistic formula: 
E = γmc^2 where γ = 1/√(1−v^2/c^2) is the Lorentz factor, m is the mass of the electron, and c is the speed of light. 
Substituting the given values, we get:
γ = 1/√(1−(0.800c)^2/c^2) = 1.67
E = (1.67)(9.11 × 10−31 kg)(3.00 × 10^8 m/s)^2 = 13.7 × 10^(-14) J
Thus, the best choice is (A) with the calculated total energy of 13.7 × 10^(-14) J.

An Electron of Mass 9