Presentation on theme: " More than 2000 years ago – Greeks discovered a rock that was attracted to materials that contained iron. MAGNETITE was this rock."— Presentation transcript:
More than 2000 years ago – Greeks discovered a rock that was attracted to materials that contained iron. MAGNETITE was this rock
LODESTONE – made from magnetite (Fe3O4) Used to make a compass used by ancient Greek & Chinese
The ability of a substance to attract iron Magnets have magnetic poles. There are two poles: 1) North Seeking Pole (NORTH) 2) South Seeking Pole (SOUTH)
The region around a magnet where the magnetic force acts & is composed of lines of force.
Opposite poles = force of attraction Like poles = force of repulsion What does that look like?
REPEL ! ATTRAC T!
This is a MRI machine. MRI stands for: Magnetic Resonance Imaging
Temporary – made by induction, magnetism that only occurs in the presence of a magnetic field Permanent – simply b/c some materials are SO influenced by magnetic fields, they become magnets themselves (Fe, Ni, Co)
Alignment of particles in the material can determine whether it will be magnetic or not.