Courbe de rayonnement du corps noir
Heat an object and it glows first red, then orange, then white. This simulation plots the full blackbody spectrum at any temperature and shows the peak sliding towards shorter wavelengths as the object gets hotter.
Comment utiliser cette simulation
- Set the temperature of the blackbody
- Overlay curves at several temperatures
- Mark the peak wavelength and the visible band
Ce qu’il faut observer
- The peak shifts towards blue as temperature rises
- Total radiated power grows dramatically — doubling T multiplies it by sixteen
- Curves at different temperatures never cross one another
La physique derrière
Planck's law gives the intensity radiated at each wavelength, producing a curve with a single peak. Wien's displacement law locates that peak at λ_max = b/T, so hotter bodies peak at shorter wavelengths. The total area under the curve — the power radiated per unit area — follows the Stefan–Boltzmann law and rises as T⁴.