magnetism

Created by

Jeraldine Dennis

Cards (95)

What do magnets produce?
magnetic fields
How many poles does a magnet have?
2, north and south
What are the two poles a magnet has?
north and south
What is a magnetic field? 
A region where other magnets or magnetic materials experience a force
What are some magnetic materials?
iron, steel, cobalt, nickel
What type of force is a magnetic field?
non-contact force
How can you show magnetic fields?
By drawing magnetic field lines
How are lines drawn on magnetic field?
North to south and show which way a force would act on north pole if it was put at that point on the field
What does it mean when the lines are closer?
The stronger the magnetic field. And vice-versa
Where is the magnetic field the strongest? 
poles of a magnet. THis means magnet forces are at it's strongest as well
What is the force between a magnet and a magnetic material?
Always attractive, no matter the pole
What happens when two poles of a magnet are put near each other?
They will exert force on each other. These are attractive or repulsive
What do two like poles do?
repel each other
What do two unlike poles do?
attract each other
What do compasses show?
The direction of magnetic fields
What is inside magnet?
Tiny bar magnet
What is the north pole of a magnet attracted to?
The south pole of aby other magnet that is near. So compass needle point in the direction og the magnetic field is in
What can you do to figure out what compass magnetic field looks like?
You can move compass around a magnet and trace needle position on some paper to build up a picture what the magnetic field looks like
When not near a magnet, where do compasses point? Why?
Point north due to earth generating its own magnetic field, which shows core of earth is magnetic
What are two types of magnets
permanent and induced
What are permanent magnets? 
Magnets that produce their own magnetic field
What are induced magnets?
magnetic materials that turn into a magnet when they're put into a magnetic field
What is the force between permanent and induced magnets?
Always attractive
When you take away magnetic field, what happens to induced mgagnets?
Quickly lose most or all of their magnetism
What does a moving charge create?
magnetic field
When a current flows through a wire, what happens?
A magnetic field is created around the wire
What is field made up of?
Concentric circles that are perpendicular to the wire. The wire is in the centre.
What happens when you place a compass near a wire carrying current?
As you move compass, it will trace direction of magnetic field
What does changing the direction of the current do?
Direction of magnetic field - use right hand thumb rule to do this
What is right hand thumb rule?
Using your right hand, point your thumb in the direction of current and curl your fingers. The direction of your fingers is the direction of the field
What does the strength of the magnetic field produce?
Changes with the current and the current and distance of the wire
What factors lead to a stronger field?
Larger the current or the closer the wire
What is a solenoid?
a coil of wire
What can you do to increase strength of magnetic field of a wire?
Creating a solenoid out of it
Why do solenoids have a stronger magnetic field?
This happens because the fields line around each loop of wire line up with each other. This results in lots of field lines pointing at each other in the same direction that are close to each other
Outside the coil, what is the magnetic field like?
Just like that of one bar magnet
How can you increase field strength of solenoid?
Putting a block of iron in the centre of the coil. The iron core becomes an induced magnet whenever current is flowing.
What happens if current stops flowing?
Magnetic field disappears
What is a solenoid with an iron core called?
an electromagnet
What is an electromagnet?
A magnet whose magnetic field can be turned on and off with an electric current