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Changing electric fields generates magnetic fields
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Changing magnetic fields generates electric fields
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Can set up a cycle where one field causes the other:
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The E and B fields oscillate in strength, and the disturbance
moves forward.
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To describe the wave you need to specify
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Direction it is moving
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Strength of the fields (its intensity)
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Frequency or Wavelength of
the oscillation ( and are inversely related)
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Orientation of the electric E field: up or sideways (polarization)
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You do not need to specify its speed
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In a vacuum all lightwaves move at
the same speed c = 3108
m/s
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