Electromagnetism Definition and 852 Threads

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. Aryamaan Thakur

    Electric potential at the edge of a thin charged circular plate

    My question might sound stupid to you but please clear my confusions. I'm taking an circular arc like element on the plate. That arc has a radius of 'r' (AB) and the radius is inclined at an angle 'θ' with OA (∠OAB). The area between arc of radius r and r+dr is dA. dA = 2θr.dr The charge on...
  2. TheBigDig

    Force on a magnet in a magnetic field

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  3. Rasias

    How to calculate what a voltmeter measures with multiple resistors?

    I tried to solve it by removing the voltmeter and simplifying it to just one resistor, then calculate the individual volts and then the deltaV, but still didn't found the answer, can you guys help me?
  4. TheBigDig

    Magnetic field of vector potential

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  5. A

    Courses Electromagnetism 1 vs. Quantum Mechanics 2

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  6. A

    Several questions about electromagnetism

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  7. K

    How Does a Dielectric Influence Charge Induction on a Conducting Shell?

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  8. K

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  9. Alex Karatzky

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  10. J

    In what direction does a light wave vibrate?

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  11. C

    Calculating Induced EMF in a Larger Solenoid Slipped Over Another Solenoid

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  12. A

    What is the electric field of a point charge?

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  13. J

    I Feynman-Heaviside formula and Mach's principle

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  14. D

    Studying John Baez's list of books math prerequisites?

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  15. li dan

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  16. li dan

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  17. E

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  18. J

    I Falling electric dipole contradicts the equivalence principle?

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  19. Javier Lopez

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  20. Lren Zvsm

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  21. A

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  22. Zack K

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  23. Cathr

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  24. F

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  25. MichPod

    I Why Not Develop Relativistic Gravitational Theory Analogy to Electromagnetism?

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  26. Ibix

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  27. Adesh

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  28. G

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  29. G

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  30. G

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  31. dRic2

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  32. R

    I Relativity and Electromagnetism

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  33. B

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  34. Faizan Samad

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  35. Cryo

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  36. P

    Free surface charges on concentric cylinders

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  37. Jozefina Gramatikova

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  38. T

    Electromagnetism Help-- Magnetostatics Boundary Problem

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  39. icesalmon

    Studying Self-Study in Electromagnetism

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  40. U

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  41. A

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  42. rude man

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  43. CDL

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  44. CDL

    Point Charges on a Polygon with another Charge in the Middle

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  45. CDL

    Studying Higher Year Physics Studies with a Shaky Foundation

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  46. G

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  47. Y

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  48. S

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  49. J

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  50. I

    Assistance with practical electromagnetism project

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