Is the Stefan-Boltzmann Law Related to Black Body Radiation?

In summary, Josef Stefan investigated the brightness of a black body as it is heated and found that the total intensity of radiation emitted over all wavelengths increases as the fourth power of the absolute temperature. This means that the power radiated per unit of area is proportional to the fourth power of the absolute temperature and the total intensity is not just the peak intensity, but a sum of all intensities from all wavelengths emitted at that specific temperature. This relationship is described by the Stefan-Boltzmann law, which states that the power radiated per unit of area is equal to the Stefan-Boltzmann constant multiplied by the fourth power of the absolute temperature.
  • #1
christian0710
409
9
Hi,

My textbooks says that "Josef Stefan investigated the increasing brightness of a black body as it is heated and discovered that the total intensity of radiation emitted over all wavelenghts increases as the fourth power of the aboslute temperature"

MY question is this: Is the "total intensity of radiation emitted over ALL wavelengths" the same as the ares (integral) underneath the Intensity vs wavelength graph that i posted underneath?

blackbody-radiation-general.png


So the "TOTAL INTENSITY" it's NOT the peak intensity but the sum of all intensities from all the wavelengths that are emittet at that specific temperature?
 
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FAQ: Is the Stefan-Boltzmann Law Related to Black Body Radiation?

What is the Stefan-Boltzmann law?

The Stefan-Boltzmann law is a physical law that describes the relationship between the temperature of an object and the amount of thermal radiation it emits. It states that the total energy radiated per unit surface area of a black body is directly proportional to the fourth power of its absolute temperature.

Who discovered the Stefan-Boltzmann law?

The Stefan-Boltzmann law was first derived by Austrian physicist Josef Stefan in 1879 and later refined by Austrian physicist Ludwig Boltzmann in 1884.

What is a black body?

A black body is an idealized material that absorbs all incident electromagnetic radiation and reflects none. It is also a perfect emitter of thermal radiation at all wavelengths, making it a useful concept in understanding the behavior of thermal radiation.

How is the Stefan-Boltzmann law used in science?

The Stefan-Boltzmann law is used in various fields of science, including astrophysics, thermodynamics, and engineering. It is used to calculate the amount of energy radiated by objects at different temperatures and to understand the thermal radiation emitted by stars and planets.

What is the significance of the Stefan-Boltzmann constant?

The Stefan-Boltzmann constant, denoted by σ, is a fundamental constant that relates the energy emitted by a black body per unit area to its temperature. It has a value of 5.6703 x 10^-8 W/m^2K^4 and is used in calculations involving the Stefan-Boltzmann law.

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