Magnetism

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Magnitude of the B-vector is proportional to the force acting on the moving charge, magnitude of the moving charge, the magnitude of its velocity, and the angle between v and the B-field. Unit is the Tesla or the Gauss (1 T = 10,000 G).

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Field Lines Around a Bar Magnet

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Field Lines Around a Magnetic Sphere

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Field Lines of Repelling Bars

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Field Lines of Attracting Bars

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Atoms themselves have magnetic properties due

to the spin of the atom’s electrons.

These areas of atoms are called “domains”

Groups of atoms join so that their magnetic fields

are all going in the same direction

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When an unmagnetized substance is placed in a magnetic

field, the substance can become magnetized.

This happens when the spinning electrons line up in the

same direction.

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An unmagnetized substance looks like this…

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While a magnetized substance looks

like this…

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How to break a magnet:

1. Drop it

2. Heat it

This causes the domains to become random again!

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Making and Breaking Magnets

In most materials, if you add energy to the electrons, you can get them to move and realign

Can you think of ways to add energy to electrons?

How can you make a magnet?

How can you demagnetize a magnet?

What happens when you break a magnet?

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Magnetic Field Vectors Due to a Bar Magnet

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