The work that must be done to increase the speed of an electron (m = 9.11 *10^-31 kg)from 0.90c to 0.95c is: A)8.2 *0^-13 J B)3.2 *10^-13 J C)2.6 * 10^-13 J D)7.4 *10^-14 J E)3.8 * 10^-15 J

Question

Quizplus · Accepted Answer

The work done on a particle is given by the equation W = ∆K = (1/2)mv², where ∆K is the change in kinetic energy. To find the work done in increasing the speed of the electron from 0.90c to 0.95c, we need to calculate the change in kinetic energy.

∆K = (1/2)m(0.95c)² - (1/2)m(0.90c)²
∆K = (1/2)(9.11x10^-31 kg)(0.95c)^2 - (1/2)(9.11x10^-31 kg)(0.90c)^2
∆K = 7.4x10^-14 J

Therefore, the work done to increase the speed of the electron from 0.90c to 0.95c is 7.4x10^-14 J. The correct choice is D.

The Work That Must Be Done to Increase the Speed