Wien’s law

Definition

Wien's law states that the wavelength at which a blackbody radiates most intensely is inversely proportional to its temperature. This means hotter objects emit radiation at shorter wavelengths.

5 Must Know Facts For Your Next Test

1. Wien's law can be mathematically expressed as λ_max = b/T, where λ_max is the peak wavelength, T is the absolute temperature in Kelvin, and b is Wien's constant (approximately 2.897 x 10^-3 m·K).
2. The law helps astronomers determine the surface temperatures of stars by examining their emitted spectra.
3. As an object's temperature increases, the peak wavelength of emitted radiation shifts toward the blue end of the spectrum.
4. Wien's law applies to idealized objects known as blackbodies, which are perfect absorbers and emitters of radiation.
5. This principle is vital in understanding various astronomical phenomena and interpreting data from telescopes observing different wavelengths.

Review Questions

Related terms

Blackbody Radiation:

The electromagnetic radiation emitted by an idealized object that absorbs all incident radiation and re-emits it perfectly.

Electromagnetic Spectrum:

The range of all types of electromagnetic radiation, from radio waves to gamma rays.

Stefan-Boltzmann Law:

A principle stating that the total energy radiated per unit surface area of a blackbody across all wavelengths is directly proportional to the fourth power of its absolute temperature.