Poles & Fields
how many poles does a magnet have
2
which is stronger? MRI magnetic field Or refrigerator magnet
MRI magnetic field
Why is a steel nail usually not a magnet?
Its magnetic domains point in different directions
What is the invisible area around a magnet where magnetic forces act?
magnetic field
name the poles of a magnet
north and south
What instrument uses Earth's magnetic field to help find direction?
compass
What is a magnetic domain?
a magnetic material where the atoms' magnetic fields point in the same direction.
name one non magnetic material
plastic/wood
north faced with south
attract
What is a compass needle actually?
small magnet
What must happen to magnetic domains for a material to become a magnet?
The domains must line up in the same direction
name one magnetic material
iron/Nickel
north faced with north or south faced with south
repel
What causes a compass needle to rotate?
Earth's magnetic field
What is a temporary magnet?
A magnet that is magnetic only while it is near another magnet
Describe two ways to increase magnetic potential energy.
opposite poles attract
same poles repel
where is the magnetic force the strongest in a magnet
at the poles
What part of Earth helps create its magnetic field?
The molten iron and nickel in the outer core
What is a permanent magnet?
A magnet whose domains remain aligned even after the magnetic field is removed.
What happens if a magnet is broken into smaller pieces?
Each piece still has a north and south pole.