Magnetism Opposites attract and likes repel What is

Magnetism “Opposites attract and likes repel. ”

What is Magnetism? A. Properties of Magnetism is the attraction or repulsion of magnetic materials Magnets attract iron and materials that contain iron Magnets attract and repel other magnets In addition, one part of a magnet will always point north when allowed to swing freely

When was Magnetism found? It was discovered by the Greeks in a town called Magnesia, where they discovered a rock called “lodestone. ” Lodestone is a natural iron ore that maintains magnetic properties.

Magnetic Poles Each magnet has 2 ends called. South Pole North Pole

Magnetic Poles that are UNALIKE attract Magnetic Pole that are ALIKE repel Magnetic Force- attraction or repulsion between magnetic poles

Magnetic Poles Magnetic Force- attraction or repulsion between magnetic poles

Magnetic Fields They are the area of magnetic force around a magnet. They spread out from one pole, curve around the magnet and return to the other pole.

Magnetic Fields A single magnetic field: A combined magnetic field:

Inside a Magnet

The Atom Magnetic properties depend on the structure of its atoms Structure of an atom:

The Atom Electron Spin- produces a magnetic field that makes the electron behave like a tiny magnet in an atom.

Magnetic Domains In a magnetized materials, all or most of the magnetic domains are arranged in the same direction. Un-magnetized Material: Magnetized Material:

Magnetic Domains Ferromagnetic Material- Latin for “ferrum, ” which means iron. Examples: iron, nickel, cobalt, Gadolinium Some magnets are made from several different metals. Examples: alloys

Making and Changing Magnets can be made, destroyed or broken Magnets can be made by placing a ferromagnetic materials into a strong magnetic field Magnets can be destroyed by dropping, hitting or heating Magnets can be broken, but keep properties

Magnetic Earth

Earth as a Magnet Earth has a magnetic field and 2 magnetic poles Earth’s core- circulation of molten rock in outer core is related to Earth’s magnetism

Earth as a Magnet Earth’s magnetic poles- they are located on Earth’s surface, where the magnetic force is the strongest. They are not aligned with the geographic poles. Magnetic Declination- the angle between geographic north and the north the compass needle points.

Earth’s Magnetic Field Since Earth has a strong magnetic field, Earth itself can make magnets out of ferromagnetic materials. Rock shows when Earth’s magnetic field was reversed through time.

The Magnetosphere Earth’s magnetic field affects the movement of electrically charged particles in space. Solar Wind- a stream of electrically charged particles flowing at high speeds from the Sun.

The Magnetosphere- the region of Earth’s field shaped by the solar wind. Aurora- a glowing region caused by charged particles