All Problems

Thermal Radiation. Quantum Nature of Light.

Problem 5.256

Transform Planck's formula for space spectral density uωu_{\omega} of radiation from the variable ω\omega to the variables vv (linear frequency) and λ\lambda (wavelength).

Reveal Answer
uv=16π2c3v3e2πv/kT1,uλ=16π2cλ5e2πc/kTλ1u_{v}=\frac{16 \pi^{2} \hbar}{c^{3}} \frac{v^{3}}{e^{2 \pi \hbar v / k T}-1}, u_{\lambda}=\frac{16 \pi^{2} c \hbar \lambda^{-5}}{e^{2 \pi \hbar c / k T \lambda}-1}