P4.1 Magnets And Magnetic Fields Flashcards
Like poles …
Repel
Unlike poles …
Attract
What are magnetic field lines?
Field lines model a magnetic field
What do magnetic field lines represent
They represent magnetic flux
What is magnetic flux density?
The number of field lines passing through a particular area
This is also called magnetic field strength
What does the density of the field lines show
They show you the strength of the field
Denser lines mean a stronger field
What is an induced magnet
A magnet that is produced when a magnetic material is placed in a magnetic field.
It may or may not stay magnetic when the field is removed
What is a permanent magnet?
A magnet that stays magnetic when other magnets or an electric current is removed
What is the remain model of magnetism
It is a model of a magnet which says that it is made up of small magnetic regions called domains
What do the domains look like in permanent magnets
Permanent magnets are made up of many domains that ALL LINE UP
What happens to the domains of a material when they are in a magnetic field (when they are induced)?
Usually their domains are not lined up but when they are in a magnetic field their domains do line up
In what direction do the field lines go on a magnet
Form north to south
What is the definition of a compass
It is a small magnet that aligns in the Earths magnetic field to show its direction
What way does a magnet point
Towards the magnetic North Pole
It is a north seeking pole
Why do scientists think that the earth has a magnetic field
It could be produced by convection currents in the molten iron core of the earth
