# Electric field

An electric field is a vector field that shows the direction that a positively charged particle will move when placed in the field. More precisely, if a particle has an electric charge ${\displaystyle q}$ and is in an electric field ${\displaystyle {\vec {E}}}$, the electric force the charge will feel is ${\displaystyle {\vec {F}}=q\cdot {\vec {E}}}$. Electric fields are produced around objects that have electrical charge, or by a magnetic field that changes with time. Electric field lines are used to represent the influence of electric field. [1] The idea of an electric field was first made by Michael Faraday.[2]

Electric fields are caused by electric charges, described by Gauss's law,[3] or varying magnetic fields, described by Faraday's law of induction.[4] The equations of both fields are coupled and together form Maxwell's equations that describe both fields as a function of charges and currents.[5]

## References

1. Richard Feynman (1970). The Feynman Lectures on Physics Vol II. Addison Wesley Longman. ISBN 978-0-201-02115-8.
2. "Michael Faraday". Retrieved 2015-06-30.
3. Purcell, p 25: "Gauss's Law: the flux of the electric field E through any closed surface... equals 1/e times the total charge enclosed by the surface."
4. Purcell, p 356: "Faraday's Law of Induction."
5. Purcell, Edward & Morin, David 2013. Electricity and magnetism. 3rd ed, Cambridge University Press. New York. ISBN 978-1-107-01402-2