HOME BLOG GITHUB
Magnetic Force Magnetic Drives Magnetic Drives Magnetic Force Magnetic Force Magnetic Drives->Magnetic Force Creating Magnetic Fields Creating Magnetic Fields Magnetic Drives->Creating Magnetic Fields Force Fields Force Fields Magnetic Drives->Force Fields Fundamental Forces Fundamental Forces Magnetic Force->Fundamental Forces Electrons Spin Electrons Spin Magnetic Force->Electrons Spin

June 01, 2020

Magnetic Force

Another force between particles.

Magnetic Force

The magnetic force is the force generated by either:

  • a charged moving particle
  • a chuck of matter than has special properties, called a permanent magnet

Moving charges

When a charge is moving, it generates a magnetic force on other particles, that is proportional to its electric charge and speed.

Permanent magnets and spins

A permanent magnet is a material that generates a static magnetic field B. These types of materials are called ferromagnetic materials and can actually be magnetized (by applying a large magnetic field on them) to become permanent magnets.

The spin of particles is responsible for the magnetic orientation of atoms. In most materials, these magnetic orientations are ordered randomly such that the resulting magnetic orientation of the material is zero. In ferromagnetic materials, the magnetic orientation of the atoms have a tendency to align with neighboring atoms. In such a case, it creates regions inside the material where the magnetic orientation is aligned. Applying a large magnetic field to these matter will cause the regions to align with each other so that the total magnetic orientation of a material is aligned to form a permanent magnet.

In summary, a ferro-magnetic material:

  • can be magnetized in order to create a permanent magnet -- a material that creates a permanent static magnetic field.
  • can be modified so that its magnetic orientation changes by applying a large magnetic field.

This allows to encode information into ferromagnetic pieces by changing the magnetic orientation / probing the magnetic field of each ferromagnetic piece.