Page 5 - Topic 3
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In the previous topic, we saw that a stationary charge will produce a stationary electric field.
Therefore it follows that a moving charge will
We saw in subtopic 2.3, that a moving electric charge will produce a magnetic field that is perpendicular to the
electric field.
We also saw in subtopic 2.5 that a changing magnetic field can induce an oscillating current or field.
This leads us to an interesting phenomena that was first theorised by James Clerk Maxwell in 1984.
An oscillating electric field creates an oscillating magnetic field. This then in turn creates an oscillating electric field
which then creates an oscillating magnetic field, and so on and so forth. These two fields are perpendicular to each
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other and they travel at a speed of 3.00 × 10 −1 in a vacuum.
This means that an oscillating charge creates an electromagnetic wave! We call this electromagnetic radiation.
