What is Magnetic force: Definition and 413 Discussions

In physics (specifically in electromagnetism) the Lorentz force (or electromagnetic force) is the combination of electric and magnetic force on a point charge due to electromagnetic fields. A particle of charge q moving with a velocity v in an electric field E and a magnetic field B experiences a force of





F

=
q


E

+
q


v

×

B



{\displaystyle \mathbf {F} =q\,\mathbf {E} +q\,\mathbf {v} \times \mathbf {B} }
(in SI units). It says that the electromagnetic force on a charge q is a combination of a force in the direction of the electric field E proportional to the magnitude of the field and the quantity of charge, and a force at right angles to the magnetic field B and the velocity v of the charge, proportional to the magnitude of the field, the charge, and the velocity. Variations on this basic formula describe the magnetic force on a current-carrying wire (sometimes called Laplace force), the electromotive force in a wire loop moving through a magnetic field (an aspect of Faraday's law of induction), and the force on a moving charged particle.
Historians suggest that the law is implicit in a paper by James Clerk Maxwell, published in 1865. Hendrik Lorentz arrived at a complete derivation in 1895, identifying the contribution of the electric force a few years after Oliver Heaviside correctly identified the contribution of the magnetic force.

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  1. L

    Magnetic force: conservative or not?

    Hi, I was thinking, velocity dependent forces such as friction are considered non-conservative. The Lorentz force on a point charge moving in a constant magnetic field depends on its velocity, so it seems the magnetic force is non-conservative. Other criteria such as vanishing curl are also...
  2. S

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  3. I

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  4. S

    How Can I Improve the Magnetic Force on a Conductor in My Physics Project?

    Homework Statement I am conceptualizing for a high school physics project and what I am currently trying to do is setup two ceramic magnets with opposite poles facing each other, but with a space in between. Next I have a wire running in between that is connected to a 1.5V power supply...
  5. N

    Magnetic force is a function of position?

    Sir,can you tell me if magnetic forces are function of position?Possibly,I read it somewhere in internet forums that magnetic forces are functions of velocity.I have read in your QM book's first page that---in microscopic level all type of force may be written as -∂V/∂x...except magnetic...
  6. mbrmbrg

    Magnetic Force to balance out Electric Force

    Homework Statement In the figure (see attatched), an electron accelerated from rest through potential difference 2.0 kV enters the gap between two parallel plates having separation 20.0 mm and potential difference 130 V. The lower plate is at the lower potential. Neglect fringing and assume...
  7. E

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  8. S

    Magnetic Force and Two Moving Charges

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  9. X

    How Does Voltage Influence Electron Motion in a Magnetic Field?

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  10. S

    Velocity Components and Magnetic Force

    Homework Statement A particle with charge 9.42×10−8 C is moving in a region where there is a uniform magnetic field with a magnitude of 0.440 T in the +x-direction. At a particular instant of time the velocity of the particle has components -v_x = 1.70×10^4 m/s, -v_y = 3.19×10^4 m/s, v_z...
  11. C

    How Do You Calculate the Angle of the Net Magnetic Force in a Complex Field?

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  12. D

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  13. D

    Max. magnetic force on an electron

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  14. D

    Magnetic Force on Electron: Unanswered Mystery

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  15. A

    Why Does Magnetic Force Behave Differently with Charges Compared to Steel?

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  16. B

    Why do magnets attract or repel each other?

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  17. S

    What is the current flowing through the aluminum rod on tilted conducting rails?

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  18. S

    Find the magnitude of the maximum magnetic force

    In a television set, electrons are accelerated from rest through a potential difference of 25 kV. The electrons then pass through a 0.26 T magnetic field that deflects them to the appropriate spot on the screen. Find the magnitude of the maximum magnetic force that an electron can experience...
  19. S

    Can SR fully explain magnetic force?

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  20. F

    Calculating Magnetic Force on a Current-Carrying Wire

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  21. S

    Max Magnetic Force Experienced by Electrons Accelerated at 19 kV

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  22. P

    What is the Magnitude of the Force on a Wire in a Uniform Magnetic Field?

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  23. P

    How Does Magnetic Force Affect a Charged Metal Ball in Motion?

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  24. K

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  25. K

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  26. U

    Finding magnetic force on two different segments

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  27. D

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  28. E

    Magnetic Force from an EM Wave

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  29. L

    What's the magnitude of the magnetic force acting on the particle?

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  30. M

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  31. K

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  32. B

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  33. M

    Magnetic Force: Halving the Distance

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  34. T

    Why Does Magnetic Force Not Alter the Speed of a Charged Particle?

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  35. P

    Asking about direction of magnetic force

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  36. C

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  37. T

    Help Solving a Problem with Cylindrical Wires: Magnetic Force Calculation

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  38. O

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  39. E

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  40. N

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  41. M

    Magnetic force on coil problem

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  42. B

    Finding Magnetic Force on a Moving Electron

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  43. R

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  44. E

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  45. F

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  46. T

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  47. S

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  48. A

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  49. V

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