Electrostatic Fields
Electrostatic fields are E-fields which do not change with time, which happens when the charges are stationary.
The electric field at a point E(r) is equal to the negative gradient of the electric potential Φ(r), a scalar field at the same point:
where ∇ is the gradient. This is equivalent to the force definition above, since electric potential Φ is defined by the electric potential energy U per unit (test) positive charge:
and force is the negative of potential energy gradient:
If several spatially distributed charges generate such an electric potential, e.g. in a solid, an electric field gradient may also be defined.
Read more about this topic: Electric Field
Famous quotes containing the word fields:
“Genius is the naturalist or geographer of the supersensible regions, and draws their map; and, by acquainting us with new fields of activity, cools our affection for the old. These are at once accepted as the reality, of which the world we have conversed with is the show.”
—Ralph Waldo Emerson (1803–1882)