# Dana A., Robin B. & Tatyana P.

## Presentation on theme: "Dana A., Robin B. & Tatyana P."— Presentation transcript:

Dana A., Robin B. & Tatyana P.
"Magnetic Interactions" What is magnetism? By: Dana A, Robin B. & Tatyana P.

Are these items magnetic or not?
Out of the few items below, can you place the items in the correct box. Magnetic Nonmagnetic

If you grouped these objects this way, then you are correct.
Magnetic Nonmagnetic At the end of the slide show, you will understand why some items are magnetic and are non-magnetic.

What is magnetism? Magnetism is the invisible force , which means that you cannot see it happening. Why? Because it is invisible. Can you see the magnet pulling the nail?

What is a magnet? A magnet is a piece of metal that can attract another piece of metal.

What do magnets look like?
Magnets can be almost any shape. Refrigerator magnets Horseshoe Bar magnet Doughnut or ring magnet Disk Magnet

Why do magnets attract or repel objects?
Pull towards object ATTRACT Pushes away object REPEL *Items that contain metals such as iron, cobalt, steel and nickel are magnetic and are therefore, attracted to magnets.

Are some of the foods we eat magnetic?
Which breakfast food do you think contains the most iron? A bagel with butter b. Waffles and syrup c. Total breakfast cereal with milk

If you guessed C, you are correct.
-Many breakfast Cereals contain iron which means that it is magnetic. -Try the experiment on the next page to see which of your favorite cereal contain iron.

Experiment: Is my breakfast food magnetic?
PROCEDURE MATERIALS 1.Place the magnet in the bowl. 2. Pour 1 cup iron-fortified cereal, such as "Total," into the mixing bowl. 3.Add 2 cups of hot water. 4. Stir the water and cereal for at least ten minutes. (Thirty minutes will give the maximum iron recovery.) 5. Carefully take the magnet out of the bowl. 6. The black residue left on the white magnet is iron. -1 Cup iron-fortified cereal (Total) -2 Cups hot water -Deep mixing bowl or glass -Spoon -White Magnet (or painted white)

The Poles of A Magnet There are two poles of a magnet.
They are North and South. The north pole is the strongest. North South

How is Earth a magnet? Earth has a north magnetic pole and a south magnetic pole. It also has an invisible magnetic field. The Earth’s core is made up of solid iron and hot liquid iron. The iron moves around as the Earth rotates. Earth’s magnetic field is called the magnetosphere.

What is a compass? -A magnet that is free to swing around. It always point to the magnetic poles. -A device used to determine geographic direction (such as North, South, East and West) usually consisting of a magnetic needle. -Many years ago, sailors used a compass to find their way at sea, today many people use navigation systems to help find their way..

What is a magnetic field?
-The lines of force surrounding a permanent magnet or a moving charged particle. These lines of force are invisible. Do the lines of force look the same? What’s different about them? Earth’s magnetic field

Do all magnets carry the same strength?
-No, some magnets are stronger than others. -A horseshoe magnet may be the strongest out of the three magnet above because the poles of the magnets are close together. -When the poles of the magnets are close together, it makes the magnet more powerful than if they were farther apart.

Can the magnets act through solids, liquids and gases?
Is the object still magnetic? Gases Paper clip YES Paper clip with a sheet of paper over it YES Solids Liquids Paper clip in a half jar of water YES

How important is magnetism in our everyday lives?
Floppy disks are made of plastic and coated in magnetic particles. Floppy disks are used to save and retrieve information. The edge of the refrigerator door is lined with a magnet. It holds the door to the metal frame. Compasses help people use the earths magnetic force to find their way. Doorbells use magnets too. The magnet pulls the hammer forward to strike the bell. Ding dong! Credit cards. The thin, black bar on the back is coated with tiny magnets. It holds information. There are tiny magnets inside a stereo, telephone, vacuum cleaner and washing machine.