Magnetic Fields

A force that surrounds a magnet or electrical field is known as a magnetic field. To get a better picture consider a magnet with a north pole and a south pole. When two magnets are joined like ends repel each other while opposite ends attract each other. The region where this takes place is known as a magnetic field.

Plasma

Plasma is the fourth state of matter. It was first discovered by Sir William Crookes in 1859. Plasmas are similar to gases but their atoms are made up of free electrons and ions of the element. Some common forms of natural plasma are stars, flames and lightning. Artificially created plasma can be found in fluorescent lights and neon signs. It is thought that up to 99% of the entire visible matter on the universe is plasma.

Motion of Charged Particles in Magnetic Fields

Particles can move through the magnetic fields of the earth in three ways:

• Spiral motion: Protons and electrons spiral up magnetic field lines. Electrons spiral the field in one direction and the protons go the opposite direction.
• Bounce motion: Due to crowded magnetic field lines near the poles of the earth, particles bounce back and forth from one pole to another.
• Drift motion: Some particles drift around the earth. Protons and electrons use opposite directions.

Source: http://www.windows.ucar.edu/tour/link=/glossary/particle_motion.html