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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?
The peak wavelength of emitted radiation shifts to shorter wavelengths (blue shift), and the total power emitted increases significantly.
What is the effect of a blackbody absorbing all incoming radiation?
The blackbody heats up and emits radiation based solely on its temperature, maintaining thermal equilibrium.
What was the effect of classical physics failing to explain the blackbody spectrum?
It led to the development of quantum mechanics and Planck's Law, which accurately describes the spectrum.
What is the effect of quantized energy, as proposed by Planck?
Energy is emitted in discrete packets (photons), resolving the ultraviolet catastrophe and accurately describing the blackbody spectrum.
What is the effect of increasing the surface area of a blackbody?
The total power emitted by the blackbody increases proportionally.
What happens when a blackbody is at a constant temperature?
It emits the same amount of energy it absorbs, maintaining thermal equilibrium.
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 constant.
The constant (b ≈ 2.898 x 10⁻³ m⋅K) that relates the peak wavelength of emitted radiation to the temperature of a blackbody.
What is the Stefan-Boltzmann constant?
The constant (σ ≈ 5.67 x 10⁻⁸ W m⁻² K⁻⁴) that relates the total power emitted by a blackbody to its surface area and temperature.
Define Planck's constant.
The constant (h) that relates the energy of a photon to its frequency (E = hf).
What is 'ultraviolet catastrophe'?
The prediction by classical physics that a blackbody would emit infinite energy at short wavelengths.