What is Electricity: Definition and 999 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. P

    Principle of superposition for charges/induced charges

    The key observation to solve the above problem is that the charge Q can be dragged out into a flat capacitor plate parallel to the 2 existing plates. Apparently, while the charge distribution on the 2 existing plates changes, the total charge induced on each plate remains the same, due to the...
  2. P

    Force needed to hold together a capacitor

    I have 2 methods, which give 2 different solutions: Let sigma = charge per unit area Let plate 1 be the left plate, plate 2 = right plate. Method 1: Because they are insulating, consider the electric field at 3 regions; region 1 to the left of plate 1, region 2 between the plates, and region 3...
  3. P

    Why is the pressure on a charged sphere only exerted on the contact area?

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  4. T

    What materials produce higher levels of static electricity?

    A lot of people know the example of a carpet and a doorknob. You accidentally rub your foot to the carpet and then get a static shock after touching the doorknob. Why does carpet produce higher static electricity than for example hardwood or something. Is it because of the hairs? Is it because...
  5. Doma Noemi

    Electricity in the human body -- Is there enough to power a prosthesis?

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  6. astrodummy

    Does electricity have a propagation delay?

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  7. L

    Can Electricity Generators Survive with LCOE Higher than Wholesale Prices?

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  8. Byron Forbes

    How Fast Does an Electrical Impulse Travel in a Copper Wire?

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  9. E

    Could you check this Li-ion charging circuit?

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  10. F

    Trying to better understand the physics of electrical earth ground

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  11. Kaushik

    Does potential drop when a charge flows through a wire w/ 0 resistance?

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  12. H

    History Why didn't ancient civilizations harness the power of electricity?

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  13. Kaushik

    Intuition about electromotive force (EMF)

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  14. Nomadyb

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  15. DerbisEternal

    How do I proceed with two different trig functions containing x on the left?

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  16. The-dude

    Static Electricity- Solving Material Placement Issues

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  17. M

    How to calculate the efficiency of a switch mode power supply?

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  18. Kaushik

    Understanding EMF and Potential Difference in Electrical Circuits

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  19. Russ Edmonds

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  20. D

    Physics Homework about using Electricity to Heat Flowing Water

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  21. Leo Liu

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  22. M

    Electricity Problem: Solutions and Causes

  23. Sokolov

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  24. E

    Nuclear Power Plants - Electricity Production

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  25. danielhaish

    Which surfaces get positively charge by grabbing (static electricity)

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  26. M

    Inducing electric current in a wire (a comparison)

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  27. D

    Turbogenerator electricity output and combustible quantity

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  28. DaveC426913

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  29. ConradG

    Why do powerplants sell electricity for a negative price?

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  30. C

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  31. T

    District heating vs. electricity generation

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  32. menniandscience

    Retarded and advanced potentials

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  33. A

    Confused about Polarization and Induction - Static Electricity

    Hello. Recently we began taking static electricity and our teacher asked us to do a research paper on static electricity and charges in general to help us understand the material better. I've been stuck a bit on trying to understand what's the difference between polarization and induction and...
  34. hiddenname

    I Electricity & Planetary Magnetic Field Reversal: Implications & Studies

    What is/are the potential or theoretical effect on electricity due to reversal of planetary magnetic field? Would circuitry continue to function or would knowledge and understanding need re-evaluating as a result of a reversal of our magnetic field on planet Earth? Note: this is not a homework...
  35. O

    I Efficiency of computers vs. brains

    Hi, I’m an undergraduate student interested in cognitive processes. I’m about to ask a very interdisciplinary question, and so hopefully I can find a physicists that can take on the challenge. What is the fundamental reason behind why modern electronic computers (transistor computers) are...
  36. I

    Inserting a dielectric material between two plates of a capacitor

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  37. D

    Joule heating effect - qualitative explanation

    Hi, I understand mathematically why using low resistance results in a greater heating effect. Could someone give an intuitive and microscopic picture of why the current contributes more to a greater power dissipation by the resistor rather than the resistance contribution to the power...
  38. R

    Can I store electricity from a wind turbine directly into a battery?

    Hello, This is an enquiry about the wind turbine electricity and battery storage. I am framing it based on my limited understanding. Please advise me. I intend to install and capture the wind energy through a small wind turbine at my home. The turbine shaft will be directly connected to the...
  39. Guidestone

    Request for historical background on the concept of voltage

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  40. atommo

    Limit to generating static electricity via contact?

    Let's say you are rubbing a balloon on your hair to make it charged. If you then discharge the balloon and rub it on your hair again (and repeat this process numerous times). Would your hair run out of electrons so eventually you would be unable to charge the balloon, or would your hair gain...
  41. jakiul094

    Electricity shared to the GRID

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  42. Superposed_Cat

    How can C4 be detonated by heat or shock, only by electricity?

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  43. E

    How would electricity be generated from a nuclear fusion reactor?

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  44. Steven Ellet

    Looking for a website or app with live chat rooms related to electricity

    I am looking for a website or app with live chat rooms related to electricity.
  45. heatupgrade

    Can we make electricity from heat?

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  46. C

    I RC charging - intuition behind equal dissipated energies?

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  47. B

    Electricity in transmission lines (Simple V^2/R =P)

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  48. B

    Electricity Circuit - Question

  49. Dr-LucienSanchez

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  50. Renewable_energyguy

    Making electricity by means of my old bike

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