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:
“I ask you to join in a re-United States. We need to empower our people so they can take more responsibility for their own lives in a world that is ever smaller, where everyone counts.... We need a new spirit of community, a sense that we are all in this together, or the American Dream will continue to wither. Our destiny is bound up with the destiny of every other American.”
—Bill Clinton (b. 1946)
“... one of the blind spots of most Negroes is their failure to realize that small overtures from whites have a large significance ... I now realize that this feeling inevitably takes possession of one in the bitter struggle for equality. Indeed, I share it. Yet I wonder how we can expect total acceptance to step full grown from the womb of prejudice, with no embryo or infancy or childhood stages.”
—Sarah Patton Boyle, U.S. civil rights activist and author. The Desegregated Heart, part 1, ch. 10 (1962)
“Your last words as you led the charge up the beach were, “Okay, men, let’s show ‘em whose beach this is!””
—Paddy Chayefsky (1923–1981)