Question

A charge of 4.845 nC is moved from a position on the y axis of 5.384 cm to a position on the x axis of 2.562 cm while there is a charge 33.053 nC located at the origin. How much work in micro-Joules did it take to move the charge?

Answer 1

Work is the change in energy

If we can find the initial state of energy and the final state of energy, we can see how much work we have to do

U= kq1q2/r

U = k(4.845x10^-9)(33.053x10^-9)/r

U = 1.44x10^-06/r

U(i) = 1.44x10^-06/5.384x10^-2 = 2.677x10^-5

U(f) = 1.44x10^-06/2.562x10^-2 = 5.626x10^-5

work = Uf - Ui = 2.949 x 10^-5 joules = 29.49 microJoules