OPT-011 · Quantum optics Sample material

Thermal radiation

Thermal radiation and the quantities describing it, blackbodies and grey bodies, the laws of Kirchhoff, Stefan–Boltzmann and Wien, the Rayleigh–Jeans formula and Planck's formula.

Estimated time: 2 h 10 min 3 activities

Learning objective

Study the quantities describing the emissive and absorptive powers of bodies.
Understand the content and consequences of Kirchhoff's law.
Apply the Stefan–Boltzmann and Wien laws in problem solving.
Understand how Planck's formula and the quantum hypothesis resolved the crisis of classical theory.

Expected outcomes

Calculates the radiant exitance and radiated power of black and grey bodies.
Finds the spectral maximum and the temperature of a body using Wien's law.
Explains the emitting and absorbing properties of bodies on the basis of Kirchhoff's law.
Compares the Rayleigh–Jeans and Planck formulas and explains the essence of the «ultraviolet catastrophe».

Interactive modelBlackbody radiation

Activities

Lecture
Lecture · 55 min · required
Thermal radiation. Regularities of thermal radiation. Blackbody radiation. The Planck and Stefan–Boltzmann laws.
Practice · 55 min · required
Final test
Test · 20 min · required · pass ≥ 70%

Completion conditions

  • Lecture
  • Thermal radiation. Regularities of thermal radiation. Blackbody radiation. The Planck and Stefan–Boltzmann laws.
  • Final test — at least 70%