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Unit 11: Magnetism Page 17
think of each atom like a little way, and contribute the magnetic
magnet. field.
However, these magnets are not all Antiferromagnetic
lined up in the same direction, so
their overall magnetic effect Some paramagnetic materials (like
cancels out. If you bring in a chromium and manganese) have
magnet (or place the atoms in a atoms pair up and cancel each
magnetic field), they start to line other out. The north pole of one
up in the same direction and the atom will line up with the south
material starts to become pole of another.
magnetized. But not quickly, or
easily, because the atoms still have Electromagnets
so much energy that they keep
bouncing around, even when in a Now we’ve covered the fact that
solid state. magnetic fields are caused by
electrons moving in the same
So to magnetize something direction. Up to this point, we’ve
quickly, you need to bring down been focusing on magnetism being
the temperature to reduce the caused by an unequal number of
motion of the atoms start to really electrons spinning in the same
line up. Paramagnetic materials are direction in an atom.
attracted to both ends of a
magnet. If an atom has more electrons
spinning in one direction than in
Ferromagnetic the other direction, that atom will
have a magnetic field. When
There are four elements bunches of these atoms get
(iron, nickel, cobalt, and together, we have a permanent
gadolinium) that most magnet. Now we’re going to talk
permanent magnets are made up about what happens if we force
of. These atoms stay lined up electrons to move.
together, even when they are at a
temperatures that would cause Moving magnets
other atoms to bounce out of create
alignment. The magnetic effects electricity?
are mostly caused by the
innermost electrons in the inner This is one of the most important
orbits, which all aligned the same scientific discoveries of all time.
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