Magnetism - Pages 582 ~ 589

DEFINITIONS
magnetic field - the distribution of a magnetic force in the region of a magnet
test compass - a compass used to check for the presence of a magnetic field
ferromagnetic metals - metals such as iron, nickel, cobalt, or mixtures of these three that attract magnets
domain theory of magnets - "all large magnets are made up of many smaller and flexible magnets that can interact with each other"
dipoles - the small and flexible magnets that make up a large magnet
magnetic domain - the effect produced when dipoles of a magnet line up
Oersted's Principle - "charge moving through a conductor produces a circular magnetic field around the conductor"
right-hand rule - a set of hand signs that allow people to take certain known factors and predict one unknown factor of magnetic forces
electromagnet - a coil of wire around a soft iron core, which uses electric current to produce a magnetic field

INFORMATION

17.1 The Magnetic Force--Another Force at a Distance

- magnetic poles of the same kind repel each other with a force a distance (N and N, S and S)
  poles with different labels attract each other with a force at a distance (N and S)

- Earth is like a giant magnet, producing its own magnetic field. It is believed that Earth's magnetic field is produced because of the flow of hot liquid metals inside Earth.

- Iron, nickel, and cobalt, or mixtures of these three are collectively called the ferromagnetic metals, and despite the fact that they are not magnets, they are still attracted by actual magnets. In fact, all magnets appear to be made up of these materials.

- According to the domain theory of magnets, "all large magnets are made up of many smaller and flexible magnets, called dipoles, which can interact with other dipoles close by. If dipoles line up, then a small magnetic domain is produced."

17.2 Electromagnets

- According to Oersted's principle, "charge moving through a conductor produces a circular magnetic field around the conductor."

- Mapping the magnetic field allows people to predict the direction of the electromagnetic force from the current, and there are right-hand rules that will help them do the mapping.

Right-hand rule #1 (RHR#1) for conventional current flow (conductors)
Right-Hand Rule #1 determines the directions of magnetic force, conventional current and the magnetic field.  Given any two of theses, the third can be found.

Right-hand rule #2 (RHR#2) for conventional current flow (coils)
Right-Hand Rule #2 determines the direction of the magnetic field around a current-carrying wire and vice-versa

Resources:
http://physicsed.buffalostate.edu/SeatExpts/resource/rhr/rhr.htm
http://www.school-for-champions.com/science/magnetism.htm