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Magnetic Forces and Fields

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Our Force Field is Magnetic!

At the present rate, Earth's magnetic field could be gone within a few centuries, exposing the planet to the relentless blast of charged particles from space with unpredictable consequences for the atmosphere and life. Other possibilities: the field could stop weakening and begin to strengthen, or it could weaken to the point that it suddenly flips polarity—that is, compasses begin to point to the South Magnetic Pole.

The Earth's Magnetic Field

Hans Christian Oersted

Origins

Comparison of force due to an Electric Field and Magnetic Field

Magnetic Force F  =  qv x B

Speaker Dynamics I

A mass spectrometer A second Mass spectrometer ANSTO

Magnetic Resonance Imaging

Magnetic Resonance Imaging Shockwave MRI

Magnetic Force on a current carying conductor

A current will make this rod move.

Which way will the loop rotate?

Motors I, II, III

Notice how the force on the top and bottom segments changes just at the right time.

Check out the Java Applets Virtual Physics Applets The Physics of: The Beautiful Aurora