What is Electric field: Definition and 1000 Discussions

An electric field (sometimes E-field) is the physical field that surrounds electrically-charged particles and exerts force on all other charged particles in the field, either attracting or repelling them. It also refers to the physical field for a system of charged particles. Electric fields originate from electric charges, or from time-varying magnetic fields. Electric fields and magnetic fields are both manifestations of the electromagnetic force, one of the four fundamental forces (or interactions) of nature.
Electric fields are important in many areas of physics, and are exploited practically in electrical technology. In atomic physics and chemistry, for instance, the electric field is the attractive force holding the atomic nucleus and electrons together in atoms. It is also the force responsible for chemical bonding between atoms that result in molecules.
Other applications of electric fields include motion detection via electric field proximity sensing and an increasing number of diagnostic and therapeutic medical uses.
The electric field is defined mathematically as a vector field that associates to each point in space the (electrostatic or Coulomb) force per unit of charge exerted on an infinitesimal positive test charge at rest at that point. The derived SI units for the electric field are volts per meter (V/m), exactly equivalent to newtons per coulomb (N/C).

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  1. A

    I Why is there no induced charge outside of the conductor?

    If we put a positive charge outside of a conductor, there is an induced charge, but if we put a positive and negative charge inside a conductor, there is no induced charge?
  2. A

    I Electric field, flux, and conductor questions

    1) Why is the electric field 0 at the bottom of Gaussian surface? Isn't the electric field on both sides of the surface, pointing down and outwards like a plane of charge? see image. 2) Why does a charge distribution with cylindrical symmetry have to be infinitely long? 3) My book says a...
  3. A

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  4. A

    I What is wrong with crossing electric fields? Why can't you sum them?

    I do not understand why electric fields cannot cross. Can't you just sum the two electric fields vectors to get a net electric field?
  5. A

    I Electric field vector takes into account the field's radial direction?

    Does the electric field vector takes into account the field's radial direction? Usually when we calculate the electric field, we use ##\vec E = \frac{kq}{r^2}\vec j##, which is a straight line vector of a positive charge q's electric field. This electric field points from a positive charge q to...
  6. A

    I Will this dipole rotate or change position?

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  7. A

    Find the electric field everywhere resulting from two infinite planes

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  8. B

    I Incident electric field attenuation near a metallic plate

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  9. J

    What is the electric field inside an infinite cylinder?

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  10. J

    Electric Field Inside a Gaussian Surface with Point Charge q

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  11. G

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  12. G

    Flux of the electric field that crosses the faces of a cube

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  13. G

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  14. G

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  15. J

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  16. S

    Exploring Electric Field Boundaries at a Charge Density Boundary

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  17. J

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  18. J

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  19. J

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  20. MatinSAR

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  21. dirb

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  22. bluesteels

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  23. R

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  24. G

    B A moving magnet in a linear electric field

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  25. guyvsdcsniper

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  26. guyvsdcsniper

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  28. emmanual

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  29. S

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  30. B

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  31. L

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  32. B

    I Estimation of E-field strength at a distance from dipole antenna

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  33. iochoa2016

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  34. Istiak

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    From the second equation I get that, ##\vec D =\frac{q}{4\pi \vec r^2}\hat r## From first equation I get that ##\vec E = \frac{q}{4\pi \vec r^2 \epsilon}=\frac{q}{4\pi \vec r^2 K \epsilon_0}## But I saw that the answer is ##\vec E=\frac{\vec E_0}{K}## While writing the comment my mind said...
  35. ilovepudding

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  36. NoahCygnus

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  37. Shreya

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  38. V

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  39. bluesteels

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  40. V

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  41. VVS2000

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  42. F

    Engineering Find the electric field intensity due to a point, line, and plane

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  43. Dario56

    I Energy Flow From Battery to the Light Bulb

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  44. F

    Engineering Calculating the charge if the electric field density = 0

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  45. Z

    On which objects can we apply Gauss' Law to find the electric field?

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  46. Z

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  47. Z

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  48. Z

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  49. F

    I Electric field of uniformly polarized cylinder

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  50. Hamiltonian

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