Magnets and Electromagnets Flashcards
How can you tell if you are holding two magnets?
Attraction occurs when there is at least one magnet.
Repulsion only occurs when there are two magnets.
What are the three elements that can become magnetic?
Iron.
Cobalt
Nickel
Which direction do magnetic field lines go?
Magnetic field lines come out of the North end of a magnet. Draw arrows on the lines.
There should be two lines coming out either end that will never touch.
What happens to a compass when there is an electric current in a wire?
If there is no current in the wire then the compass will be unaffected.
If there is a current which is going in the same direction as the compass, the compass will turn to the left.
If the current is reversed , the compass will turn to the right.
A good way to see which way the compass will turn is to use your right hand in the shape of a thumbs up. Your thumb will be the direction of the current and the direction your knuckles is the direction the compass will turn.
What are the magnetic domains of a magnet?
Most materials don’t have magnetic domains. The only ones that do are iron cobalt and nickel.
Without magnetic domains, a material isn’t magnetic and will never be magnetic.
A piece of iron has magnetic domains that are all facing different directions. When a magnet comes near the iron, the domains all face the direction of the magnet which allows them to stick together.
A magnets domains are all in lines facing the same direction which allows the material to be magnetic.
