What is Electromagnatism: Definition and 66 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. M

    I Is the electromagnetic 4-vector indeed a 4-vector?

    About the electromagnetic 4-vector ##A^\mu=(\Phi/c,\mathbf{A})##. If it is indeed a four-vector, then its squared length ##A_\mu A^\mu=\Phi^2/c^2-\mathbf{A}^2## should be a Lorentz invariant. What is the physical significance of ##\Phi^2/c^2-\mathbf{A}^2##? Thanks for any help.
  2. A

    Flux linked with circular coil vs solenoid

    $$E_{max}=N^2πr^2Bω=N×0.603V$$ $$<E_{avg.}>=<N^2πr^2Bω\sin⁡(ωt)>=E_{max.}<sin⁡(ωt)>=0$$ $$I_{max.}=N×0.0603A$$ Average Power loss=$$\frac{<(E_{ind}^2)>}{R}=N^2×0.018W$$ The correct solutions are : ##0.603## ,##0## ,##0.0603##, ##0.018## Why am I gettting an extra N? Is the emf of thin circular...
  3. butterflycandy

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  4. E

    Is total flux linkage λ=dΨ*Ienclosed/I or λ=N*Ψ?

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  5. S

    B Homopolar motor rotation in Vacuum

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  6. milkism

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  7. G

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  8. H

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  9. W

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  10. Salmone

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  11. physicks885

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  12. godiswatching_

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  13. Dom Tesilbirth

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  14. S

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  15. H

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  16. U

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  17. R

    How far do gamma rays extend from an accelerator?

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  18. S

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  19. J

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  20. dom489

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  21. astroman707

    Studying What's the best way to apply the concepts learned in physics 2?

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  22. P

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  23. JD_PM

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  24. A

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  25. Silverhobbiest

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  26. thariya

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  27. T

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  28. astroman707

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  29. A

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  30. A

    I Does the color of an object change as it gets hotter?

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  31. S

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  32. H

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  33. S

    How to calculate total cross section from differential cross section

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  34. Toby_phys

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  35. F

    Please clear my electromagnetism doubt about units

    It is a well known fact that, in electromagnetic units, strength of a shell and strength of current flowing through its boundary are same. See here. \begin{equation} \begin{matrix} \text{i.e.}\: i \text{(biot)} = \phi \text{(biot) } \end{matrix} \tag{1} \end{equation} (a) While converting to...
  36. Zohaib_aarfi

    I Correct relation is F^{ij} = - epsilon^{ijk} B^k.

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  37. L

    How do I apply Maxwell's equations?

    For example, if I have a magnetic field perpendicular to some surface and I change this magnetic field with constant speed, how do I calculate the Electric field at any point on this surface, since ∫E⋅ds=k, where k is some constant, could be done with many different vector fields.
  38. Angelo Cirino

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    I am reviewing Jackson's "Classical Electromagnetism" and it seems that I need to review vector calculus too. In section 1.11 the equation ##W=-\frac{\epsilon_0}{2}\int \Phi\mathbf \nabla^2\Phi d^3x## through an integration by parts leads to equation 1.54 ##W=\frac{\epsilon_0}{2}\int |\mathbf...
  39. A

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  40. V

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  41. AaromTheBritt

    I Remembering Lenz's Law: An Easier Way?

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  42. D

    How photons exceeds their velocity?

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  43. O

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  44. physicality

    I How to show that Electrodynamics is conformally invariant?

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  45. S

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    Homework Statement Two coencenteric metalic shell has inner radius $r_1$ outer radius $r_2$. We place along axis infinity wire has $\lambda$ charge in per unit length. The inner region of metalic shells inserted with relative permabilitty coefficent $\epsilon$. This system rotates with $\omega$...
  46. fabiogn

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  47. AmishaPanchal

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  48. Titan97

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  49. DrPapper

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  50. recursive

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