WELCOME BACK MINIONSGet ready for some magnetism!

WHAT DO WE KNOW?• What are the properties of magnets?

• How do magnetic poles interact?

• What is the shape of a magnetic field?

DEMONSTRATION!!!• Where does each magnet hold the greatest number

of paper clips?

• What are the similarities between the bar magnet and the horseshoe magnet?

A MAGNETIC HISTORY…• More than 2000 years ago.

• Greek city of Magnesia (now Turkey)• Discovered an unusual type of rock

• Attracted to materials containing iron!• About 1000 years ago

• People discovered another property• When tied to a string it pointed in one direction!

• Toward the north star, Polaris.• Star is called the leading star or lodestar

• This stone is referred to as a “lodestone”!

MAGNET• Magnet

• Any material that attracts iron or any material that contains iron.

• Properties• Attracted to iron or any material that contains iron.• Attract or repel other magnets.• Always point north when allowed to swing freely.

MAGNETIC POLE• No matter what shape, every magnet has two ends.

These ends are known as the Magnetic Poles.

• The magnetic effect are strongest at the poles.

• The Pole that points north is the North Pole while the pole that points south is the South Pole.

MAGNETIC INTERACTIONS

• Magnetic Force• The attraction or repulsion between magnetic poles.

MAGNETIC FIELDSMagnetic field lines spread out from one pole, curve

around the magnet, and return to the other pole.

MAGNETIC FIELDSWhen the magnetic fields of two or more

magnets overlap, the result is a combined field.

SINGLE MAGNETIC FIELD

COMBINED MAGNETIC FIELD

WRAP-UP• What is a Magnet?

• Any material that attracts iron or any material that contains iron.

• What are 3 properties of a Magnet?• Attracted to iron or any material that contains iron.• Attract or repel other magnets.• Always point north when allowed to swing freely.

• What will happen to a bar magnet that is allowed to swing freely?• The North pole of the magnet points north!

TICKET OUT OF THE DOOR…

• What are the properties of magnets?

• How do magnetic poles interact?

• What is the shape of a magnetic field?