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. S

    I Gravitational analog of electromagnetic force

    Is there a gravitational analog of electromagnetic force? [Apart from the obvious "static" forces, ie electrostatic between fixed charges and gravitational between fixed masses.] I am thinking of the classic situation of a moving charge (or current) creating a magnetic field which then...
  2. hagopbul

    I Asking about something that I read on electromagnetic force

    Hello All: read a paper related to electromagnetic force and its applications in acceleration of charges particles , some thing came up in it , they drive a force applied on the particle called Faraday force = [1/2B]* [dB/dt]*m*v B magnetic field , m mass of the particle , v the velocity of...
  3. Woomir

    I Why is my magnetic levitation experiment not working?

    [Mentor Note -- Two similar thread starts merged into one] Hey all, I have been working on this project for a while now, which features suspending an object midair through the use of magnetic levitation principles. Cool right? And so I have been researching and trying, even finding ground...
  4. rudransh verma

    Contact and electromagnetic force

    I don’t know what is contact force. Are friction and normal forces called contact forces? And we have to take the resultant of the two to get the net contact force?
  5. N

    B Electromagnetic force of Electrons

    If you could command all the electrons in an average human body and get them to spin in synchronicity (a clockwise circle in the horizontal plane) how much magnetic force does that produce? Would it create a force against gravity and make you feel lighter? How much lighter?
  6. R

    How to find electromagnetic force between nucleus and electron?

    Hello, I'm new here and honestly I'm not a physics student. I'm studying engineering and so, understand little of physics. I am trying to find the bond force of graphene's free electron. That means, the electromagnetic force by which the electron is bound to the nucleus. I can only calculate it...
  7. Amoghgirgaonkar

    The Mystery of Purple Objects: Understanding Electromagnetic Force

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  8. MacGyver Megh

    B The electromagnetic force of quarks

    If an up quark has 2/3 of positive charge and down quark has 1/3 of negative charge then why don't they add together by their electromagnetic force?
  9. B

    A How does the electromagnetic force influence a galaxy (if at all)?

    Like what are the chances that dark matter can be described with electromagnetism instead?
  10. B

    Please explain "Electromagnetic force is mediated by light"

    We have talked about light behaving as a wave and a particle. Having trouble understanding what 'mediated' means in this context.
  11. M

    How close does an electron get to a proton to be attracted

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  12. gibberingmouther

    Line Integral for Electromagnetic Force

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  13. C

    Monitor restarts when I make an electric arc

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  14. F

    Electromagnetic force on particles forming a square

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  15. P

    Find the magnitude of the electromagnetic force on electron?

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  16. C

    Amount of excess charge to overcome Earth's gravity

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  17. mertcan

    How Is the Red Part of Stratton's Equation Derived from Light Pressure?

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  18. Incnis Mrsi

    A Chirality of the electromagnetic force on atomic matter

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  19. T

    Stopping the Slowdown: Electricity & Electromagnetic Force

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  20. facenian

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  21. tzukishiro

    I Why is the weak force 10^-7 times the electromagnetic force?

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  22. Einstein's Cat

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  23. Einstein's Cat

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  24. N

    Calculating Spring Constant and Forces in an Electromagnetic System

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  25. N

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  26. P

    How Does QED Explain the Electromagnetic Force

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  27. U

    Cross Section for e+e- in EM interaction - Is it the same?

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  28. L

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  29. A

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  30. M

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  31. T

    About the photon exchange and the electromagnetic force

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  32. R

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  33. C

    Origins of the electromagnetic force

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  34. O

    Calculating Electromagnetic Force at 0 Distance?

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  35. D

    Electromagnetic force between Parallel Currents

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  36. F

    Calculating Electromagnetic Force on a Moving Wire

    Homework Statement A wire of length L=20cm travels with an acceleration a=0.002m/s2 perpendicular to the Earth's magnetic field (B=20μT). Considering that the wire starts from rest, calculate the value of the emf (electromagnetic force) when an hour has gone by. Homework Equations My...
  37. S

    Can Parallel Charged Particles Maintain Their Speed in Space?

    Homework Statement when two like charged particles are traveling in space on parallel tracks, exert electric and magnetic forces on each other, then what is their speed when they continue to move in the parallel track? Homework Equations since both are lick charges there should be a...
  38. Q

    Feynman Diagram for Electron-Proton Attraction

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  39. H

    Calculate electromagnetic force on iron object

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  40. umair20

    How friction is an electromagnetic force?

    how friction is an electromagnetic force?
  41. C

    Help With Electromagnet and Air Cores

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  42. J

    How do we know gravity is not just a large scaled electromagnetic force?

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  43. A

    How photon is force carrier of electromagnetic force in macroscopic level.?

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  44. D

    Is this a valid equation for determining electromagnetic force?

    I have been searching the internet for a simplistic equation which is capable of calculating the force of an electromagnet. I think I have found one at http://www.ehow.com/how_5969962_calculate-force-electromagnet.html however am not entirely sure this is a correct equation (don't really trust...
  45. C

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  46. B

    Electromagnetic force required to levitate an object

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  47. P

    How Does Mass Affect Electromagnetic Attraction and Repulsion?

    First: Since photons carry electromagnetic force between charged particles, and the gravitational force is presumably separate (at least at typical energy levels) then is it correct that an object's mass is irrelevant in considering electronic(electromagnetic) attraction/repulsion? i.e. an...
  48. B

    Electromagnetic force and some trig

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  49. M

    Which is an example of the electromagnetic force?

    This was a question on an online homework for a modern physics class. I had two chances to answer it, but I was wrong both times, so I'm simply curious what the answer is. Homework Statement The Attempt at a Solution (a) Quarks attracted to one another is the strong force (b) A...
  50. P

    Electromagnetic force question

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