Download Magnetism

Magnetism
• How do magnets interact with each
other?
Key Question
• If a material is magnetic, it has the ability to exert forces
on magnets or other magnetic materials.
• A permanent magnet is a material that keeps its magnetic
properties even when it is NOT close to other magnets.
What is a magnet?
• Magnets have two
opposite poles.
• North
• south
• Magnets exert forces on
each other.
• The forces depend on the
alignment of the poles.
Properties of Magnets
• Magnets must have a north pole and a south pole
• If you cut a magnet in half, the resulting pieces have a
north and south pole each
• There is no such thing as a magnetic ‘monopole’
Properties of Magnets
• All magnets create a magnetic field in the space around them, and
the magnetic field creates forces on other magnets.
• Magnetic field lines always point away from a magnet’s north pole
and toward its south pole.
• The closer the lines are together, the stronger the field.
• The number of field lines in a certain area indicates the relative
strength of the magnetic field in that area.
Magnetic Field
• Whenever there is a moving electric charge, there is a
magnetic field and an electric field
• Bring a compass near a current carrying wire and you will
see the compass deflect
• Once the electric charge stops moving, the magnetic field
dissapates
Magnetism and
Electricity
• Permanent magnets can induce
magnetic properties in certain
materials.
• The furthermost point must have the
opposite pole of the opposite side
• Remember, no magnetic monopoles
Magnetic Induction
Magnets, How do they
work?