Magnetism

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S

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Magnetic Field Lines

The direction of the magnetic field at any point is tangent to the magnetic field line at that point.

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Vocabulary for ELL

Magnet: material that can both attract and repel other magnets. Iron is most common.

Pole: Part of the magnet where the force is the strongest

Metal: material that is often attracted to magnets and a good electrical conductor

Horseshoe magnet:

U-shaped magnet

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The Earth is a magnet

It exerts magnetic forces and is surrounded by a

magnetic field that is strongest near the

North and South

magnetic poles

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Sometimes, the Earth’s magnetic poles flip. This happens every half-million years or so.

Magnetic North Pole

Magnetic South Pole

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We use the Earth’s magnetic field

to find direction.

The needle of a compass always points toward the magnetic south pole.

We call this direction “North”

(remember, opposites attract)

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Vocabulary for ELL

Geographic North pole: the north end of the axis around which the Earth rotates

Magnetic North pole: the point on the Earth to which a compass needle points

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The sun has a magnetic field, too. It extends far above the sun’s surface.

Other planets in the solar system also have these magnetic fields

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When a charged particle enters a magnetic field, an electric force is exerted on it. If a charged particle moves at an angle to a magnetic field, the magnetic force acting on it will cause it to move in a spiral around the magnetic field lines.