Year 8 Term 1 - Magnetism Flashcards
Name 4 magnetic materials
Iron, cobalts, nickel, steel
Name 2 non-magnetic materials
Copper & aluminium
What’s the difference between a magnet and magnetic material
Magnetic materials only attract
Magnets attract and repel and have a north and South Pole.
Where is magnetism strongest
At the magnet’s poles.
Like poles always ….
Opposite poles always…
Repel
Attract
Both poles always……..
Attract unmagnetised magnetic materials
How do you induce poles
Temporary poles must be induced on unmagnetised magnetic materials when they are brought towards a magnet
Is the force stronger or weaker the closer you are to a magnet
Stronger
How do you know if a material is magnetic?
It attracts to the magnet
How do you know if a material is not magnetic
The material neither attracts nor repels to the magnet.
How do you test if a magnetic material is a magnet
Bring, in turn, a north and south pole close to the material, If it is a magnet, one side should attract and other repel, but if it is just an unmaAgnetised magnetic material it will attract from both sides.
How do you investigate the variation of force with distance from poles (closer the stronger/weaker etc)
Use a balance; the pushing force is being measured so to get a higher reading you would need to hold the magnet further away
As the distance increases, the force on the magnet is not as strong
What is a magnetic field?
The space around a magnet where the forces are felt
Basic design of a magnetic field
Curves up out of north and into south
____________)
(. V
<—— out of north [. Magnet ] <—— into south
(. ^
~~~~~~~~~~~~
Curves up and out of north into south
What is a compass
A bar magnet that is free to spin so that it lines up with magnetic fields
How do you make a compass
Place a bar magnet on two watch glasses, and the magnet should spin and point due north due to the fact there is NO FRICTION.
True or false: the earth doesn’t have a magnetic field
False
What creates earths magnetic field
It is created by its liquid iron core spinning which lines up the magnetic particles.
Which way does a compass point
Due north.
How to make a permanent magnet
Take a hard magnetic material (e.g steel)and stroke it in one direction with the north end of a magnet
How do you make a temporary magnet
You have to induce temporary magnetism - using another magnet (induce poles)
Take a soft magnetic material and attach a magnet to one end of it - when you remove it it goes back to being non magnetic
How do you make an electromagnet
You need a direct current (battery) and wrap wire around the soft magnetic material (nail) and it creates a current.
What is the difference between hard and soft magnetism
Hard magnetism is difficult to magnetise/demagnetise and soft magnetism is the opposite.
Hard magnetism: once it’s a magnet it stays a magnet.
Give an example of hard magnetism
Cobalt
