The frequency is defined as the rate at which wave crests pass a fixed point. The frequency equals the speed of light divided by the wavelength. Figure 3- Physics of Radiation Properties of Radiation Warmer bodies radiate at shorter wavelengths than cooler bodies. The wavelength which is radiated by an object depends on the object's temperature. The warmer the object, the shorter the wavelength.
Warmer bodies radiate more energy than cooler bodies.
The energy emitted from an object is proportional to the fourth root of the object's temperature. Good emitters are good absorbers at a particular wavelength. Poor emitters are poor absorbers at the same wavelength. Figure 4- Reflection, Absorption, Scattering, Refraction, and Transmission Radiative Transfer Radiation can be absorbed, reflected, scattered, refracted, or transmitted.