The name is absent

Electric field

The electromagnetic field is composed from electric and magnetic field. The
electric field could be described via vector field of the electric intensity E . The
electric intensity is defined as the ratio of the electric force F_E acting upon
charged body and the charge q of the body.

——             ——

^— _l.   ∆ FE   dFE

E = lim —E- = —E

∆q→0 ∆qdq

It should be noted that the electric field is potential field - that is the work W
along closed contour Γ is zero.

W_γ = c∫) dW = 0

Γ

(f FE ∙ dl = 0

Γ

where l is the length of the contour Γ.

Every point from the electric field has electric potential V defined with the specific
(for unit charge) work needed to carry a charge from this point to infinity. The
electric potential of point c of given electric field has potential V defined by:

(6)                V = ∞ E ∙ dl + K

c

where V_∞ =K=0 . The electric potential difference between two points 1 and 2
defines voltage ∆V (synonyms: electric potential, electromotive force, potential,
potential difference, potential drop).

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