Figure 1-Sum 7. Use of a Prism to Split White Light into Different Colors
The primary colors of light are red, green, and blue. These primaries can be
mixed to make any color between red and violet. If the three colors are mixed
equally, they produce white light.
The complementary colors of light are magenta, yellow, and cyan. Mixing any
two of the primary colors together in overlapping beams produces them.
The speed of light in empty space is considered to be 186,000 miles per second
(or 300,000,000 meters per second). This speed varies in different mediums,
but the constant of 186,000 miles per second is always used as the speed of
The electromagnetic spectrum is the complete range of electromagnetic
frequencies from 3 kHz to beyond 300,000 THz. Audio frequencies (15 Hz to
20 kHz) are not electromagnetic energy and are not included in the
electromagnetic spectrum. The electromagnetic field consists of an electric
field and a magnetic field. These fields are responsible for the transmission
and reception of electromagnetic energy through free space.