I understand that the filament is heated by resistance and glows indandescently. What is the actual mechanism for the emission of light by incandescence? Are the electrons actually excited to higher energy levels or is something else going on?
It's a great question and when it was first considered it kick started quantum theory. May I suggest that you start by googling the black body radiation curves.Thank you for your replies. That is interesting about the vacuum thanks. What is the actual mechanism of black body emission?