What is Electric: Definition and 1000 Discussions

Electricity is the set of physical phenomena associated with the presence and motion of matter that has a property of electric charge. Electricity is related to magnetism, both being part of the phenomenon of electromagnetism, as described by Maxwell's equations. Various common phenomena are related to electricity, including lightning, static electricity, electric heating, electric discharges and many others.
The presence of an electric charge, which can be either positive or negative, produces an electric field. The movement of electric charges is an electric current and produces a magnetic field.
When a charge is placed in a location with a non-zero electric field, a force will act on it. The magnitude of this force is given by Coulomb's law. If the charge moves, the electric field would be doing work on the electric charge. Thus we can speak of electric potential at a certain point in space, which is equal to the work done by an external agent in carrying a unit of positive charge from an arbitrarily chosen reference point to that point without any acceleration and is typically measured in volts.
Electricity is at the heart of many modern technologies, being used for:

Electric power where electric current is used to energise equipment;
Electronics which deals with electrical circuits that involve active electrical components such as vacuum tubes, transistors, diodes and integrated circuits, and associated passive interconnection technologies.Electrical phenomena have been studied since antiquity, though progress in theoretical understanding remained slow until the seventeenth and eighteenth centuries. The theory of electromagnetism was developed in the 19th century, and by the end of that century electricity was being put to industrial and residential use by electrical engineers. The rapid expansion in electrical technology at this time transformed industry and society, becoming a driving force for the Second Industrial Revolution. Electricity's extraordinary versatility means it can be put to an almost limitless set of applications which include transport, heating, lighting, communications, and computation. Electrical power is now the backbone of modern industrial society.

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  1. joyxx

    Why are transformers important to electric power distribution

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  2. J

    What is the minimum charge needed for a ball to jump in an electric field?

    I don't really know how to fit what i want to this template, but i'll try. The thing is that i wonder if anyone can explain to me step-by-step what happened in this solution, because i don't really understand it. Homework Statement There are two balls. Upper one(mass m, charge Q) hung on a...
  3. R

    Do photons carry the electric field?

    In basic electrostatics any charged particle will produce an electric field at every point in space, and will have electric filed lines spreading out radially. E = kQ/r^2 The Standard model of particle physics says that the Photon is the force carrier for the Electromagnetic force, just like...
  4. Suyash Singh

    Electricity and Electric field

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  5. W

    Phase relation between the electric & magnetic fields in a plasma

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  6. J

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  7. A

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  8. D

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  9. R

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  10. Prof Sabi

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  11. J

    Using Kirchoff's Loop Rule to Determine Currents in a Circuit

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  12. Pratik007789

    Homework Help: Find the Electric Flux Through a Hole In a Sphere

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  13. P

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  14. W

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  15. S

    Electric Field of a Line of Charge

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  16. E

    Finding the electric field at point - Can someone check my work?

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  17. Ignitia

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  18. S

    Maximum electric field from magnetic field

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  19. J

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  20. T

    Getting electric potential from charge density over whole sp

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  21. B

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  22. F

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  23. L

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  24. F

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  25. F

    Find the electric field of a point P at a distance r

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  26. W

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  27. F

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  28. Sunanda

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  29. S

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  30. F

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  31. D

    Calculating the magnitude of the total electric field at P

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  32. A

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  33. K

    Is the Setup for the Electric Scaler Potential Integral Correct?

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  34. B

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  35. S

    Electric Field induced by a Magnetic Field inside a Solenoid

  36. A

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  37. A

    Determining the direction of electric field lines

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  38. A

    How does the transfer of electric forces between two objects work

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  39. D

    Electric Potential Question

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  40. Stephenk53

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  41. Paola Flores

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  42. G

    Using Gauss's Law to Calculate Electric Field of a Charged Thread

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  43. C

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  44. Y

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  45. C

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  46. H

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  47. B

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  48. C

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  49. jedishrfu

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  50. radiant_june

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