P4.1

Created by

khadijah<3

Cards (31)

what are the ends of a magnet called?
poles
the law of magnetism states that 2 of the _____ poles repel each other
same
the law of magnetism states that two _________ poles attract each other
opposite
are magnetic materials attracted to magnets?
yes
are non-magnetic materials attracted to magnets?
no
examples of magnetic materials
iron, cobalt, nickel and steel
why is steel magnetic?
it is an alloy, which contains iron
magnetic materials will always be attracted to the magnet, regardless of which pole is held close to it.
how can we test whether a material is magnetic?
bring it close to a known magnet
if it can be repelled, the material itself is a magnet
if it can only be attracted, then it is a magnetic material
what are the 2 types of magnets?
permanent and induced
what are permanent magnets made of?
magnetic materials e.g. steel
what is the key feature of a permanent magnet?
it produces its own magnetic field and will not lose its magnetism
how are induced magnets created?
when a magnetic material is placed in a magnetic field, the material can be temporarily turned into a magnet
magnetic materials will always be attracted to a permanent magnet. this means that
the end of the material closest to the magnet will have the opposite pole that it is next to.
what happens when a magnetic material is removed from the magnetic field?
it loses all/most of its magnetism quickly
what is a magnetic field?
the region around a magnet where a force acts on another magnet / magnetic material
what do you use to show the direction of the magnetic field?
arrows
how is the strength of a magnetic field shown?
by the spacing of the magnetic field lines
if the magnetic field lines are close together, the magnetic field is?
strong
if the magnetic field lines are far apart, the magnetic field is?
weak
what is the direction of the field lines?
always go from north to south
where is the magnetic field the strongest?
poles
what type of magnetic field is produced in the gaps between opposite poles?
uniform
how can we prove that the core of the earth is magnetic?
in the absence of any magnet or magnetic materials, a magnetic compass will always point north.
when is a magnetic field produced around the wire?
When current flows
how can we work out the direction of the magnetic field?
using the right-hand thumb rule
point the thumb along the direction of the current
the other fingers curl around to give the direction of the field
what does a circle with a dot show?
current is flowing out of the plane
what does a circle with a cross show?
current flowing into the plane
what factors affect the strength of a magnetic field?
the size of the current and the distance from the long straight conductor (e.g. a wire)
what is a solenoid?
a wire coiled up into a spiral shape
how can we increase the strength of the magnetic field around a solenoid?
increase the size of the current flowing through the wire
increase the number of coils
add an iron core through the centre of the coils