15
Magnetism & Electromagnetism The Nature of Magnetism Chapter 1 Section 1

Magnetism & Electromagnetism The Nature of Magnetism Chapter 1 Section 1

Embed Size (px)

Citation preview

Page 1: Magnetism & Electromagnetism The Nature of Magnetism Chapter 1 Section 1

Magnetism & Electromagnetism

The Nature of Magnetism

Chapter 1

Section 1

Page 2: Magnetism & Electromagnetism The Nature of Magnetism Chapter 1 Section 1

Magnets

• Magnetism– The attraction of a

magnet to another object

Page 3: Magnetism & Electromagnetism The Nature of Magnetism Chapter 1 Section 1

Magnesia (in Greece)

• Used over 2,000 years ago

• Magnetite– Mineral found in some

rocks

– Fe3O4

• Attracts iron

Page 4: Magnetism & Electromagnetism The Nature of Magnetism Chapter 1 Section 1

Lodestones

• Magnets swinging on strings will eventually point toward the …– Lodestar

• Means Leading Star– Aka North Star

• Discovered 1,000 years ago

Page 5: Magnetism & Electromagnetism The Nature of Magnetism Chapter 1 Section 1

Magnetic Poles

• The area of the magnetic where the magnetic effect is strongest

• North Pole• South Pole

Page 6: Magnetism & Electromagnetism The Nature of Magnetism Chapter 1 Section 1

Interactions Between Poles

• Like poles repel, Unlike poles attract

Page 7: Magnetism & Electromagnetism The Nature of Magnetism Chapter 1 Section 1

Breaking a Magnet

• Produces smaller magnets

Page 8: Magnetism & Electromagnetism The Nature of Magnetism Chapter 1 Section 1

Magnetic Fields

• The magnetic force exerted all around a magnet

• Magnetic Field Lines– Spread out from one

pole, curve around the magnet and return to the other pole

– Never cross

Page 9: Magnetism & Electromagnetism The Nature of Magnetism Chapter 1 Section 1

Elements

• One of about 100 basic material that make up all matter

• Atom– The smallest particle

of an element

Page 10: Magnetism & Electromagnetism The Nature of Magnetism Chapter 1 Section 1

In an Atom

• Bigger, in Nucleus– Protons

• “+” charge

– Neutrons• No charge

• Electrons– Small– “-” charge– Orbits nucleus

• Produce a small “Atomic Magnetic Force”

Page 11: Magnetism & Electromagnetism The Nature of Magnetism Chapter 1 Section 1

Magnetic Domain

• A cluster of billions of atoms that have magnetic fields that are lined up in the same way

• Magnetized Material– All/most of the

domains are arranged in the same direction

Page 12: Magnetism & Electromagnetism The Nature of Magnetism Chapter 1 Section 1

Ferromagnetic Material

• A material that shows strong magnetic effects

• Iron, Fe• Nickel, Ni• Cobalt, Co

Page 13: Magnetism & Electromagnetism The Nature of Magnetism Chapter 1 Section 1

Making Magnets

• Some materials can be magnetized if rubbed with a strong magnet– Typically just

temporary

• Magnetic Domains become aligned

Page 14: Magnetism & Electromagnetism The Nature of Magnetism Chapter 1 Section 1

Destroying Magnets

• Knocking the domains out of alignment

• Drop it• Strike it• Heat it

Page 15: Magnetism & Electromagnetism The Nature of Magnetism Chapter 1 Section 1

MagLev

• 400 km/hr– 250 mph

• Floats a few cm’s above tracks– No vibrations– No noise from the

steel tracks