What is Electromagnetism: Definition and 838 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. L

    Geometric product in electromagnetism

    Hi. I've been learning how to use geometric algebra and I've been stumbling when I apply it to E&M. I am hoping someone here can point out what I am doing wrong. The problem comes when trying to represent the field tensor in terms of the 4-potential. Here is the standard form: F^{\mu\nu}...
  2. M

    Curvature of path made by electron in electromagnetism

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  3. fluidistic

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  4. T

    MIT series on Electromagnetism

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  5. L

    Electromagnetism- current carrying conductor and permanent magnet

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  6. MathematicalPhysicist

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  7. PrincePhoenix

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  8. A

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  9. S

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  10. MathematicalPhysicist

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  11. A

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  12. R

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  13. S

    Is gravity really just an electromagnetic field on a larger scale?

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  14. D

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  15. F

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  16. T

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  17. Y

    Electromagnetism and Magnetic Flux in a Rectangular Circuit: Homework Help

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  18. F

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  19. P

    Prerequisites for Electromagnetism?

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  20. MTd2

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  21. S

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  22. E

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  23. J

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  24. P

    Electromagnetism Explaining Question

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  25. N

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  26. I

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  27. P

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  28. C

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  29. snoopies622

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  30. S

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  31. F

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  32. Phrak

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  33. Phrak

    Three Laws of Classical Electromagnetism

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  34. L

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  35. C

    Is Electromagnetism Relative and Does it Create a Paradox in Moving Frames?

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  36. R

    What is the Total Force on a Wire Segment in a Uniform Magnetic Field?

    1. "A wire segment carries a current of 1.8A from a to b. There is a uniform magnetic field of 1.2T acting in the z-direction. Find the total force on the wire and show that the total force is the same as if the wire were a straight segment from a to b". I've attached the diagram showing what...
  37. L

    Calculating Electrostatic Energy for a Uniformly Charged Sphere?

    A sphere of radius R has a unifromly distributed charge Ze inside it (essentially it's a model of a nucleus) now my tutor worked through the first part of the question with me and we established that the potential inside the sphere was \varphi(\mathbf{r})=-\frac{Zer^2}{8 \pi \epsilon_0...
  38. N

    Electromagnetism question (Stump book) - Dielectric

    Ok this book is very common. It's the question number 6.5 A dielectric object that has a quasi-permanent polarization when the applied field is 0 is called an electret. Consider a uniformly polarized electret in the shape of a cylinder of height h and radius 10h. The polarization in the...
  39. J

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    Homework Statement When a uniform electric field is applied to diamond, the induced dipole moment per unit volume (ie. polarisation) is P_{0} = 1.5 \times 10^{-7} \text{C m}^{-2}. Given that the density of diamond is 3500 \text{kg m}^{-3}, 1 kmole of diamond has a mass of 12kg. Avogadro's...
  40. N

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  41. C

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  42. S

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  43. H

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  44. K

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  45. K

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  46. C

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  47. C

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  48. J

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  49. D

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  50. C

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