Already a member? Login
Already a member? Login
A magnet is something that can attract certain metals.
Magnets have many uses. They stick things on, hold things together, and make machines work.
Do you have magnets on your refrigerator?
Do your cabinets have magnets that hold the doors shut?
Do you have speakers in your home? These are made with magnets, too.
Did you know that almost every machine in your house has magnets in it?
Let's explore the world of magnets!
Some rocks are natural magnets.
Here's a story about magnets:
Long ago, a boy in Ancient Greece walked across a big rock.
There were iron nails in his shoes that kept them together. But as he walked across the rock, it pulled the nails right out. His shoes fell apart, and the nails stuck to the rock!
We don't know if this story is true or not.
But we do know that the word magnet comes from the name of a place, Magnesia, where some of these natural magnet rocks were found.
No, there are only certain metals that are attracted to a magnet.
They are iron, nickel and cobalt. These metals can become magnets.
Magnets come in different shapes.
They can be bar magnets, horseshoe magnets, or ring magnets as shown in the picture below. (Notice the north and south poles in each type of magnet.)
A magnet has two ends. These are called the magnet's poles. One is called the north pole and one is called the south pole.
You can see that different poles of a horseshoe magnet attract each other in the picture below.
The north pole of a magnet attracts the south pole of another magnet. (That means it pulls the magnet toward it.)
And the south pole of a magnet attracts the north pole of another magnet.
But magnets don't just attract. They can also repel, or push things away.
The poles that are the same repel each other.
So a north pole would repel another north pole and a south pole would repel another south pole as you can see below.
The attraction and repulsion of a magnet is due to an invisible field around it, called the magnetic field.
Is the strength of this magnetic field same everywhere in a magnet?
Let's find this out by bringing some iron filings close to a bar magnet. Now, observe carefully.
You can see that more iron filings are attracted to the ends of the magnet, while less iron filings are attracted to its center.
This shows that strength of this magnetic field is more at the ends and less at its center.
Have you ever seen a compass?
A compass is a tool that helps people know which direction they're going.
A compass has a needle that has been made into a magnet. (You can make something into a magnet by rubbing it with a magnet.)
The needle in the compass can spin.
The needle spins so that one end of the magnet points to the north and one to the south.
This works because the earth is like a big magnet!
There is iron inside the earth. That gives our planet its magnetic field.
Do you know about the Northern Lights and the Southern Lights?
They are natural light displays in the sky-almost like fireworks!
They can be seen in the areas around the north and south pole. They are caused by the Earth's magnetic field.
Sometimes the sun throws out a burst of energy.
These bursts get caught in the magnetic field around the earth.
They give off some beautiful, bright colors.
The Northern and Southern Lights are one of the ways we know that earth is a big magnet!
Magnets can pull through the earth's atmosphere.
It can also pull through solids like paper and liquids like water.
As we've seen, magnets are useful, powerful, and sometimes amazing. Look around you and see how many ways magnets are used!
A. Which one is a magnet?
What you need:
What to do:
B. What does a magnet attract?
What you need:
What to do:
C. Can a magnet work through objects?
What you need:
What to do:
D. The north and south poles of a magnet
What you need:
What to do:
E. Measure the strength of a magnet
What you need:
What to do: