All Flashcards
Describe how a blackbody reaches thermal equilibrium.
A blackbody reaches thermal equilibrium when it emits the same amount of energy it absorbs, maintaining a constant temperature.
Outline the process of energy emission according to Planck's Law.
Energy is emitted in discrete packets (quanta) called photons, with energy E = hf, where h is Planck's constant and f is the frequency.
What is the effect of increasing the temperature of a blackbody on its emitted radiation?
As temperature increases, the peak wavelength shifts to shorter wavelengths (blue shift), and the total power emitted increases significantly.
What is the effect of increasing the surface area of a blackbody on its power emission?
Increasing the surface area of a blackbody directly increases the total power emitted, as described by the Stefan-Boltzmann Law (P = AσT⁴).
Define Blackbody Radiation.
Electromagnetic energy emitted by an object due to its temperature.
What is a Blackbody?
An idealized object that absorbs all incoming radiation and emits energy based solely on its temperature.
Define Wien's Displacement Law.
The wavelength at which a blackbody emits the most radiation is inversely proportional to its temperature.
What is the Stefan-Boltzmann Law?
The total power emitted by a blackbody is proportional to its surface area and the fourth power of its absolute temperature.
Define Planck's constant.
The constant that relates the energy of a photon to its frequency ().
What is 'ultraviolet catastrophe'?
The prediction of classical physics that a blackbody would emit infinite energy at short wavelengths.