Free, Bound and Total Charge
In dielectric materials, the total charge of an object can separated into "free" and "bound" charges.
Bound charges set up electric dipoles in response to an applied electric field E, and polarize other nearby dipoles tending to line them up, the net accumulation of charge from the orientation of the dipoles is the bound charge. They are called bound because they cannot be removed: in the dielectric material the charges are the electrons bound to the nuclei.
Free charges are the excess charges which can move into electrostatic equilibrium, i.e. when the charges are not moving and the resultant electric field is independent of time, or constitute electric currents.
Read more about this topic: Charge Density
Famous quotes containing the words bound, total and/or charge:
“Without being bound to the fulfillment of promises, we would never be able to keep our identities; we would be condemned to wander helplessly and without direction in the darkness of each man’s lonely heart, caught in its contradictions and equivocalities—a darkness which only the light shed over the public realm through the presence of others, who confirm the identity between the one who promises and the one who fulfills, can dispel.”
—Hannah Arendt (1906–1975)
“When we suffer anguish we return to early childhood because that is the period in which we first learnt to suffer the experience of total loss. It was more than that. It was the period in which we suffered more total losses than in all the rest of our life put together.”
—John Berger (b. 1926)
“The Germans are called brutal, the Spanish cruel, the Americans superficial, and so on; but we are perfide Albion, the island of hypocrites, the people who have built up an Empire with a Bible in one hand, a pistol in the other, and financial concessions in both pockets. Is the charge true? I think it is.”
—E.M. (Edward Morgan)