planck's law

planck's law : For a general introduction, see black body. In physics, Planck's law describes the spectral radiance of electromagnetic radiation at all wavelengths from a black body at temperature $T$. As a function of frequency $\backslash nu$, Planck's law is written as: This function represents the emitted power per unit area of emitting surface, per unit solid angle, and per unit frequency. Sometimes, Planck's law is written as an expression $u(\backslash nu,T)\; =\; \backslash pi\; I(\backslash nu,T)$ for emitted power integrated over all solid angles. In other cases, it is written as $u(\backslash nu,T)\; =\; 4\backslash pi\; I(\backslash nu,T)/c$ for energy per unit volume. The function $I(\backslash nu,T)$ peaks for h$\backslash nu$ = 2.82 kT. It falls off exponentially at higher frequencies and polynomially at lower. As a function of wavelength λ, Planck's law written (for unit solid angle) as: This function peaks for hc = 4.97λ kT, a factor of 1.76 shorter in wavelength (higher in frequency) than the frequ....   More from Wikipedia

planck's law : Wien's displacement law states that the blackbody curve at any temperature is uniquely determined from the blackbody curve at any other temperature by displacing, or shifting, the wavelength. The average thermal energy/frequency in each mode with frequency $\backslash nu$ is only a function of..   More from Wikipedia

  Cal Teach student assistant Kibeum Ryoo does an activity on infrared star detection with students at the 2009 BCCP Cosmology Workshop. An experiment using an infrared thermometer that simulated Infrared Spectroscopy illustrated a fundamental concept of black body radiation. In this activity, students use an Infrared thermometer to simulate how infrared telescopes determine the temperature of stars. In physics, Planck's law describes the spectral radiance of electromagnetic radiation at all ...

  the 18th century philosophy of determinism born from Newtonian physics, and how this philosophy was shattered by discoveries beginning in the 20th century. (2/10) The discovery of the particle nature of the photon by Max Planck, von Lenard, and Albert Einstein. Plancks law of black body radiation, von Lenards photoelectric effect, and Einsteins interpretation of the photoelectric effect are all covered. We finish with the particle wave duality introduced by Louis de Broglie. (3/10) ...