Magnetism: Force of attration or repulsion cause by the movement of charged particles
It is not a charge
It's caused by the movement of a charge
Magnetic Poles: A region on a magnet which produces magnetic forces
The poles of a suspended magnet will align themselves to the poles of the earth
Magnetic Field: The space around a magnet in which a magnetic force is exerted
-The shape of a magnetic field is revealed by magnetic field lines
--Directed away from north poles and toward sourth poles
The strength of magnetic fields are measured in units of Tesla (T)
Caused by the motion of electric charges
-Since motion is relative, so are magnetic fields
Magnets at rest consist of charges in motion
-Every spinning electron is a tiny magnet
-Electrons spinning in the same direction produce a stronger magnet
Clusters of aligned atoms
Permanent magnets are made by placing materials in strong magnetic fields
-Aligns the domains
It is possible to weaken a magnet by dropping or heating it
-Pushes domains out of alignment
Magnetic Poles are located:
North: Hudson Bay region of northern Canady (1800km from geographic pole)
South: Just south of Australia
Magnetic Declination: Difference between geographic and magnetic poles
The magnetic field of Earth reverses on an irregular cycle
1 million years ago, the field completely "shut off" for 10,000-20,000 years
Its strength has decreased by 5% over the last 100 years
-Indicates a reversal possibily in the next 200 years
Electromagnet: A current-carrying coil of wire with many loops
-The magnetic domains of a piece of iron placed in the coil will be aligned
-This will intensify the magnetic field
-The strongest electromagnets use superconductors as a core