The Basics
What is a Magnetic Field?
At the very basic level, a magnetic field is a field produced by an electric current. Magnetic fields are dipolar, most widely represented with a north and south pole. The Earth’s magnetic field is similar to one produced by a bar magnet that has been tilted approximately eleven degrees. More specifically, a magnetic field is a vector field, which means that every field interacts in some way with every part of the universe.
Plasma!
Plasma, often considered the fourth state of matter, is simply a gas that has been heated so much that it becomes ionized. The atoms from the gas actually lose one or more electrons under the extreme heat, producing the plasma phase state. The free electric charges that ensues makes plasma electrically conductive, which in turn makes plasma respond powerfully to magnetic fields.
Charged Particles and Magnetic Fields
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A charged particle feels a force when it moves through a magnetic field. As no work can be done on a particle by a magnetic field, a particle’s speed cannot be changed by a magnetic field, only its direction of movement. Instead of doing work, magnetic fields can instead influence already existing forces, causing those forces to do work on a particle. |
Important Original Scientists in the Field
- James Clerk Maxwell- Developed equations expressing the laws of magnetism and electricity.
- Sir William Crookes- Perhaps the first person to observe the fourth phase, plasma, in a laboratory.