The mass of an electron is about 9.11 × 10-31 kg. Write this as a whole number

1 electron has a mass of 9.1 X 10-31 kg. How many electrons n does it take to make 1 kg?

(1 e)/(9.1 X 10-31 kg) = n/(1 kg)

So, n = 1.10 X 1030 electrons

Each electron has a charge of 1.6 X 10-19 C, where C stands for Coulombs. So, the n electrons have a charge of q = ne = (1.10 X 1030 electrons) X (1.6 X 10-19 C/electron) = 1.76 X 1011 C. This is an insane charge!

The electrostatic force between two of these 1kg bundles of electrons is given by Coulomb's law:

F = k qq/r2 = (8.99 X 109)(1.76 X 1011 C)2/(1000 m)2 = 2.78 X 1026 N.