Lecture
This lecture covers the radiative properties of small and large particles, focusing on Rayleigh and Mie scattering theories. The instructor begins by discussing the absorption coefficient and scattering efficiency factors, using examples such as the burning of propane to illustrate these concepts. The lecture emphasizes the importance of the size parameter, which is the ratio of the wavelength to the particle size, and how it influences scattering behavior. The instructor explains Rayleigh scattering, particularly its dependence on wavelength, and describes the phenomenon of color changes during sunset due to this scattering. The transition to Mie theory is introduced, which applies to larger particles and provides a more complex understanding of scattering. The lecture also addresses the geometrical optics limit for large opaque spheres, detailing how reflection and diffraction play roles in scattering. Throughout, the instructor encourages students to engage with the material and seek clarification on complex topics, ensuring a comprehensive understanding of the principles involved in radiative properties and scattering phenomena.