A natural Magnet, magnetite or Lodestone Fe3O4

Chinese South Pointer

Circa 1100 A.D.

Earth Globe with strong magnet inside. The staples align with the field.

Gilbert made a sphere of magnetite and used small iron rods to explore its magnetic force.

He discovered that the reason magnetic compass needles pointed north was that the earth was a magnet.

Here the equator is vertical.

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Magnetic Sandon

Radar Magnetsmade of AlNiCo

Black magnetite sand follows magnetic field lines.

Field lines Michael Farady

Magnetic Bacteria navigate using the Earth’s magnetic field.

Magnetotacticum AquaspirillumBlack crystals are magnetite.

The magnetic field of

the earth deflects

ionic particles

in the solar wind.

Earth, north and south aurora

Jupiter Aurora

Saturn Aurora

Solar Magnetic field lines.Plasma follows the field lines.

The magnetic field lines that come up out of the center magnet curve around and down on its

sides exerting an upward force on the adjacent magnets.

Iceland, Ingolsfjall moberg, a volcano born inside a glacier.

Iceland, Ingolsfjall moberg, Top 1/2 current magnetic fieldBottom half reversed.

Antarctic lava flowNear Mt. Morning.

Geologist marks magnetic north on a bedrock sample

Theoretical model of a possible flip of the earth’s field.

Pieces of magnetic cassette tape record magnetic fields

Magnetic stripes in ocean floor lavas.

USGS Menlo Park magnet laboratory.

Magnetic stripes on Mars

What is magnetism?

Electric charge at rest Electrostatics

Electric charge: Constant speed

Magnetism

Electric charge:Accelerating

Electromagnetic Radiation

An Electromagnet.

All magnetism comes from

moving electric charges or changing

electric fields.

Every iron atom is a magnet. Atoms align in domains. In a nonmagnetic piece of irons the direction of domain magnetization is random.

See Magnetic domains

Grapes are Diamagnetic, repelled by both magnetic poles

Oxygen in the air is paramagnetic, attracted to a magnet.

The flame is low in oxygen and experiences a bouyant force away from the magnet.

QuickTime™ and aYUV420 codec decompressor

are needed to see this picture.

A ball of water (with green dye added) is diamagneticaly suspended in a magnet.

QuickTime™ and aYUV420 codec decompressor

are needed to see this picture.

A magnetically levitated frog.

A human in a magnetic resonance imager.

Whole Body MRI

Graphite levitated over a strong magnetic track.

A magnet guided down

a track.

A NIB magnet falling

between two aluminum plates falls

slowly due to electromagnetic induction.

Drop ZoneCars are stopped by magnet induced eddy currents.

Electric Guitar