Page "Electromagnetic field" Paragraph 4

Classically, electric and magnetic fields are thought of as being produced by smooth motions of charged objects.

For example, oscillating charges produce electric and magnetic fields that may be viewed in a ' smooth ', continuous, wavelike fashion.

In this case, energy is viewed as being transferred continuously through the electromagnetic field between any two locations.

For instance, the metal atoms in a radio transmitter appear to transfer energy continuously.

This view is useful to a certain extent ( radiation of low frequency ), but problems are found at high frequencies ( see ultraviolet catastrophe ).