What is Electricity and magnetism: Definition and 214 Discussions

Electromagnetism is a branch of physics involving the study of the electromagnetic force, a type of physical interaction that occurs between electrically charged particles. The electromagnetic force is carried by electromagnetic fields composed of electric fields and magnetic fields, and it is responsible for electromagnetic radiation such as light. It is one of the four fundamental interactions (commonly called forces) in nature, together with the strong interaction, the weak interaction, and gravitation. At high energy, the weak force and electromagnetic force are unified as a single electroweak force.

Electromagnetic phenomena are defined in terms of the electromagnetic force, sometimes called the Lorentz force, which includes both electricity and magnetism as different manifestations of the same phenomenon. The electromagnetic force plays a major role in determining the internal properties of most objects encountered in daily life. The electromagnetic attraction between atomic nuclei and their orbital electrons holds atoms together. Electromagnetic forces are responsible for the chemical bonds between atoms which create molecules, and intermolecular forces. The electromagnetic force governs all chemical processes, which arise from interactions between the electrons of neighboring atoms. Electromagnetism is very widely used in modern technology, and electromagnetic theory is the basis of electric power engineering and electronics including digital technology.
There are numerous mathematical descriptions of the electromagnetic field. Most prominently, Maxwell's equations describe how electric and magnetic fields are generated and altered by each other and by charges and currents.
The theoretical implications of electromagnetism, particularly the establishment of the speed of light based on properties of the "medium" of propagation (permeability and permittivity), led to the development of special relativity by Albert Einstein in 1905.

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  1. Z

    What is the induced magnetic force on this closed current loop?

    Below I will go through derivations I saw in some notes from MIT OCW's 8.02 "Electricity and Magnetism". We thus have a closed loop. Let the normal vector be ##\hat{n}=\hat{k}##. Then, the area vector is ##\vec{A}=A\hat{k}##. The magnetic flux through this loop is...
  2. M

    What is the net force on the current loop?

    The long wire carrying ##5A## current causes a non-uniform magnetic field whose formula is known. I calculated the force exerted by this magnetic field on each of the four sides of the rectangular loop and summed them up. I got the right answer, but a question is nagging me---doesn't the loop...
  3. O

    Understanding the energy of a dipole in a uniform electric field

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  4. S

    Solid State Researching Gold Thin Films: Electrical & Optical Properties

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  5. dliu1004

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  6. Z

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  7. B

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  8. Viona

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  9. P

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  10. P

    Principle of superposition for charges/induced charges

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  11. yyfeng

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  12. P

    Position for maximum electric field between two wires

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  13. P

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  14. tanaygupta2000

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  15. Luke Tan

    Charge Inside a Cavity in a Conductor

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  16. T

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  17. H

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  18. S

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  19. Hawkingo

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  20. Taxi1337

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  21. Zack K

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  22. P

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  23. P

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  24. Silentwhale

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  25. Silentwhale

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  27. starstruck_

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  29. starstruck_

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  30. shahbaznihal

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  31. A

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  32. starstruck_

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  33. Gene Naden

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  34. F

    I Please suggest whether I should use delta or dx method.

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  35. M

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  36. Fraser MacDonald

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  37. astrocytosis

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  38. S

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  39. S

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  40. L

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  41. A

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  42. C

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  43. J

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  44. egio

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  45. V

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  46. lz975545

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  47. bananabandana

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  48. N

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  49. M

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  50. G

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