What is Electromagnetic force: Definition and 77 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. N

    How can we unify electromagnetic force U(1) and weak force SU(2)?

    Please teach me this: How can we unify electromagnetic and weak interactions?Is it correct that the SU(2) symmetry(flavor symmetry of fermions) is spontaniously broken(by Higgs Field) and the symmetry(be broken) ''become'' U(1)xSU(2) symmetry that is the symmetry of electroweak interaction...
  2. A

    How Virtual Particles Give Rise to the electromagnetic force

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  3. S

    Work done by electromagnetic force

    Homework Statement 1.Calculate the work done by the force F=i cos(pix/4) + j y2 along the path y=x2 in the x-y plane from (0,0) to (2,4). 2.Is the force F conservative? Explain. Homework Equations Work = Integration between a and b of F.dl The Attempt at a Solution 1. I know...
  4. Y

    Getting lorentz electromagnetic force from hamilton principle

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  5. B

    No Electromagnetic Force in Moving Magnet & Solenoid

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  6. S

    Best way to route electromagnetic force.

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  7. X

    What are the different types of electromagnetic forces?

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  8. D

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  9. M

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  10. M

    Determining electromagnetic force and fields

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  11. S

    How Do Photons Carry Electromagnetic Force?

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  12. K

    Electromagnetic force calculation

    Hi, I understand that force due to an electromagnetic field on a surface can be calculated by F = \oint {T . n dS} where T is Maxwell stress tensor. http://en.wikipedia.org/wiki/Maxwell_stress_tensor" And this tensor consists of E_x, E_y, E_z, H_x, H_y, H_z I don't understand how...
  13. PrincePhoenix

    Electromagnetic force and resistance to displacement of atoms.

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  14. P

    When does gravitational force = electromagnetic force?

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  15. S

    Electromagnetic force in the fourth spatial dimension?

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  16. S

    Electromagnetic Force: Where Does Virtual Photon Get Its Energy?

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  17. M

    Electric and Electromagnetic force

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  18. M

    Question about electromagnetic force and mass

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  19. F

    Why Are Rubbed Plastic Pieces Attracted to Each Other?

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  20. K

    Current producing electromagnetic force

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  21. D

    'pull' & 'push'- electromagnetic force?

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  22. C

    Whats reverse electromagnetic force?

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  23. L

    Why do we need a photon to mediate the electromagnetic force?

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  24. E

    Mediation of the electromagnetic force

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  25. B

    Electromagnetic force in electric motor

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  26. A

    Electromagnetic Force Problem -

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  27. K

    What Would Happen to Electromagnetic Force in 4D?

    I hope my question makes some sense; if not, just post an "evil smiley" and ignore it :smile: So, my only "knowledge" about this is based on one of Hawking's books, wherein it is written: If space had four dimensions instead of three, gravitation would behave differently (I think it was...
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