This energy, or radiation, is emitted as electromagnetic waves that travel at the speed of light . Many different types of radiation have been identified. Each of these types is defined by its wavelength . Some of the various types of electromagnetic radiation as defined by wavelength.
Visible light is a form of electromagnetic radiation that can be perceived by our eyes.
Figure 4f-1 illustrates that various spectral color bands that make up light. Solar radiation spans a spectrum from approximately 0.1 to 4.0 micrometers. The band from 0.1 to 0.4 micrometers is called ultraviolet radiation . The amount of electromagnetic radiation emitted by a body is directly related to its temperature. This natural phenomenon is described by the Stephan-Boltzmann Law .