Download 2.1.4 magnetic fields

Definition : A magnetic field is a force field which
surrounds either a magnet or a wire carrying an
electric current and will act upon, without contact,
another magnet or current carrying wire
Plotting Compass
Like the other fields we have studied we represent
magnetic fields diagrammatically using field lines or
lines of magnetic flux
We name the ends of a magnet “the poles”.
(North and & South). More correctly they
should be referred to as the “North seeking
pole” and “South seeking pole”
Like poles repel
each other
Unlike poles
attract each
other
The arrows on a magnetic field line represent
the path which a “tiny free north pole”
would take
The Earth has a
magnetic field
just like a giant
magnet.
The geographic
North pole has
a South
magnetic pole
associated with
it (Since a
north seeking
pole of a
magnet will
point towards
it) Earth Dipole
Watch
terminology!!!
At the
geographic
North pole
there is a
magnetic pole
which we can
refer to as
“Magnetic
North”.
However it is
a South pole!
Watch the
field lines!
Wires carrying a magnetic current produce a
magnetic field
“Maxwell’s corkscrew rule” can be used to
establish the direction of this field. Note the
current direction is the direction of
“conventional current” positive to negative