Aperson scuffing her feet on a wool rug on a dry day accumulates a net charge of -70.1 uc. by how much does the mass of the person increase?

First, the charge of the electron e = -1.602 x 10^-19 Net Charge Q = -70.1 uC Mass of the electron m = 9.1 x 10^-31 kg Number of Electrons is net charge divided by electron charge N = -70.1 / -1.602 x 10^-19 => N = 70.1 x 10^-6 / -1.602 x 10^-19 N = 4.375 x 10^14 So calculating the increase in mass = N x mass of the electron, m => N x m = 4.375 x 10^14 x 9.1 x 10^-31 = 39.8 x 10^-17