4.3: Thermal Radiation
An object’s temperature is the measure of the speed at which the object’s particles move. To measure temperature, astronomers prefer the Kelvin temperature scale . This scale is much like Celsius, but 0 o is Absolute Zero – scale starts at zero, 0K. Wien’s Law relates the color of an incandescent object to its temperature. The law states that wavelength of the brightest color is inversely proportional to the object’s temperature.
Where:
-
Stefan-Boltzmann Law
states that the power,
P
, emitted per unit of area of an object is proportional to the fourth power of its temperature,
T
. Mathematically, this is:
- P is the power
- T is the temperature