What is Electrical: 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. nmaganzini

    Electrical Engineering PhD application

    Hi guys, I am a senior EE undergrad at UCLA and will be graduating this spring, 2016. I am applying for PhD programs in EE with a focus on biomedical devices (implantable devices and/or sensor networks and embedded systems). I am choosing which schools to apply to and would like your advice...
  2. S

    Engineering Working Abroad for Electrical Engineering - What to Know?

    Hello, I graduated from an accredited University in Canada with a Bachelor of Science in Electrical Engineering. I maintained Honours with Distinction for the duration of my academic career. I am interested in working abroad, and branching from Canada. I am not sure where I want to go yet...
  3. N

    Electrostatic discharge current

    I understand that electrically charged objects such as a rubber balloon or even the human body can hold several thousands of volts. What's troubling me is that I know the current that results from an electrostatic discharge is not enough to cause serious damage or kill a human, yet if you touch...
  4. vision99

    Engineering What are the recent advances in electrical engineering?

    What is new, in the field of electrical engineering? Thanks, doug
  5. supak111

    Help me design a simple time delay (not electrical)

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  6. U

    How do arc furnaces sustain themselves without significant resistance?

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  7. G

    Engineering Electrical Engineering to Computer Science

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  8. M

    Electrical engineering with mechanical interest...?

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  9. D

    Does electrical conduction require energy state changes?

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  10. TMECLT

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  11. J

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  12. E

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  13. N

    Similarity between P&ID and Electrical diagrams?

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  14. T

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  15. Lokesh7890

    Can Electrical Signals Be Converted to Sound and Used to Read Minds?

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  16. Y

    How Can I Solve an Electrical Machine Theory Problem Without a Solutions Manual?

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  17. P

    Electrical Potential Energy of three quark system

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  18. V

    Engineering Electrical Circuits - Network/Transfer Function

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  19. T

    Electrical meter and efficiency question

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  20. O

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  21. N

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  22. Y

    Engineering Electrical Engineering - AC Circuits Phasors

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  23. B

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  24. Y

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  25. J

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  26. Y

    Engineering Electrical Circuits - Three Phase Power - Y-Y transformer

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  27. E

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  28. G

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  29. K

    Calculating the Effective Spring Constant of a Charged DNA Molecule

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  30. AdoobII

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  31. C

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  32. M

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  33. S

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  34. H Smith 94

    Electrical conductivity of seawater depends on salinity how?

    Hi! I am currently trying to determine how the salinity ##S## of a sample of seawater (or, objectively, a salt-water solution) changes its electrical conductivity ##\sigma##. It is clear that they are proportional since the mobility of the ##\text{Na}^{+}## and ##\text{Cl}^{-}## ions plays a...
  35. A

    QM for electrical engineering?

    Hi there PFers I'm looking into a variety of areas of research in electrical engineering at US universities. For instance, looking at the University of Texas page, there's a research specialty in EE called "plasma/quantum devices and optics." Now, this looks very interesting to me. I was...
  36. A

    Difference between electrical and thermal faults?

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  37. R

    Automatic electrical switch to between two paths

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  38. E

    Engineering General engineering with specialization in electrical

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  39. S

    Electrical Can I Use JB Weld to Build DIY High Voltage Vacuum Feedthroughs?

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  40. H

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  41. L

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  42. ryanuser

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  43. 2

    What subjects to focus on as an EE interested in Aerospace?

    Hello, I am currently pursuing my BS in EE. I am interested in avionics and would like to eventually work in the aerospace industry. What sort of topics should I focus on? I did an initial search on the forums and people have noted that these subjects are relevant: - Control Systems -...
  44. CiscoCertified

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  45. Y

    Engineering Can I pursue MS electrical, electronics & computer engineering?

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  46. T

    Engineering Second Bachelors in Electrical Engineering at FIU?

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  47. AceTrainerBlue

    Computer Engineering - Electrical Eng. & Computer Science?

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  48. N

    Engineering How much electrical engineering in taught in Ms Mechatronic?

    I have always been interested in Engineering and a while back I could not decide between Electrical and Mechanical. However, I chose Mechanical, but now that I see that almost every invention nowadays are in electrical engineering field (I want to be an inventor) I am upset! So anyhow I was...
  49. Guidestone

    Strange questions about electrical circuits

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