Magnetism Flashcards
What is magnetism?
Magnetism: an invisible force that pushes or pulls magnetic material.
What is a magnet?
Amagnetis a material that produces a magnetic field.
Which metals are magnetic?
Only iron (Fe), nickel (Ni) and cobalt (Co) are magnetic
Are non-metals (e.g. wood and plastic) magnetic or non-magnetic?
Non-magnetic. They are not attracted by a magnet.
What are the ends of a magnet called?
Poles (North pole and South pole)
Opposite poles of magnets (N and S) will _____________.
Attract
Like poles (e.g. N and N) of magnets will _____________.
Repel
Permanent magnets are usually made from which material?
Steel
Name 3 uses of a permanent magnet.
- Compasses
- Toys
- Fridge magnets
- School lab experiments etc
What is an electromagnet?
Electromagnets use electricity to create a magnet from a current-carrying wire
Name an advantage of an electromagnet.
They can be magnetised and demagnetised.
i.e. They can be switched on and off.
Which metal is usually used to form an electromagnet?
Iron
Why is iron use in electromagnets?
It can easily become a temporary magnet
What are some uses of electromagnets?
- MRI scanners
- Speakers and earphones
- Sorting out recycled goods
- Mag-Lev trains
etc
Define the term ‘magnetic field’.
The region around a magnet where a force acts on another magnet or on a magnetic material (such as iron, steel, cobalt and nickel)
What do magnetic field lines show us?
Magnetic field lines are used to represent the strength and direction of a magnetic field
What are the rules when drawing magnetic field lines?
1) Always go from north to south (indicated by an arrow midway along the line).
2) Must never touch or cross other field lines.
Where on a bar magnet is the magnetic field the strongest?
The magnetic field is strongest at the poles
This is where the magnetic field lines are closest together.
What is a magnetic material?
A magnetic material is a material that is attracted to a magnet e.g. iron
What is a non-magnetic material?
A substance that is not attracted to a magnet e.g. paper, wood, glass
On Earth, the north arrow on a magnetic compass will point towards the geographic __________ Pole (in the Arctic Ocean)
North
What is a permanent magnet?
Are magnets that produce their own magnetic field, can attract or repel other magnets.
What is an induced magnet?
Materials that can become a magnet when placed in a magnetic field. Lose their magnetism when removed from a magnetic field.
Where is the magnetic field the strongest?
The magnetic field isstrongest at the poles
This is where the magnetic field lines areclosesttogether.