Magnetism Flashcards
what is a permanent magnet
always produce a magnetic field
what is an induced magnet
become magnatised when in another magnet
what metals can become magnatised
iron
colbolt
nickel
what metals can not become magnatised
aluminium and copper
what happens to a electric current flowing through a wire
will produce its own magnetic field
what is the motor effect
when a current flowing wire is in another magnetic field it will experience a force
how to calculate force f=bil
magnetic flux density(b - tesla) x current x length
what will happen between the forces in an induced magnet and a permanent magnet
they will always be attracted
what does being magnetically soft mean
lose their magnetism really quickly (nickel and iron)
what does being magnetically hard mean
lose magnetism slowly (steel)
what will the field lines look like in a wire that has a current flowing through it
circles closest together near to the wire as that is where the magnetic field is strongest
what is the right hand rule
put right hand into fist where the thumb is pointing up to the current the other fingers will show the direction of the magnetic field
what happens to the magnetic fields in a circular coil
they interact and become
stretched out to form ellipses
they then combine and form one magnetic field with a straight line in the middle
what is a solenoid
wire coiled up into spiral shape
what are the properties of a magnetic field in a solenoid
strong
uniform