Charge conservation elementary charge on positive and negative particles must be extremely close to equal, differing by no more than a factor of 10 for the case of protons and electrons. Ordinary matter contains equal numbers of positive and negative particles, protons and electrons, in enormous quantities. If the elementary charge on the electron and proton were even slightly different, all matter would have a large electric charge and would be mutually repulsive. The best experimental tests of electric charge conservation are searches for particle decays that would be allowed if electric charge is not always conserved. No such decays have ever
Induced-charge electrokinetics Induced-charge electrokinetics Induced-charge electrokinetics in physics is the electrically driven fluid flow and particle motion in a liquid electrolyte. Consider a metal particle (which is neutrally charged but electrically conducting) in contact with an aqueous solution in a chamber/channel. If different voltages apply to the end of this chamber/channel, electric field will generate in this chamber/channel. This applied electric field passes through this metal particle and causes the free charges inside the particle migrate under the skin of particle. As a result of this migration, the negative charges moves to the side which is close to the positive (or higher)