A simple experiment employing low cost apparatus is presented which demonstrates the falloff of intensity with distance and the transition from the near field to the far field of a line source filament incandescent light bulb. A derivation of the Poynting vector as a function of the distance away from the filament is presented which shows an exact correspondence to the derivation for the electric field from a finite line charge source in electrostatics. The experimental data of power vs distance from the filament show an inverse first power of the distance falloff in the near field, with a smooth transition to an inverse square law behavior in the far field, in good agreement with the theoretical expression when corrections for the measured angular response of the detector are included. The experiment provides an illustration of the inverse square law falloff of intensity at large distances from the source, experience with simple concepts and techniques of optical radiometry and incoherent light sources, and the analogy between incoherent light sources and electrostatics in an undergraduate laboratory. An additional short experiment provides an illustration of electrical‐to‐optical power conversion efficiency and temperature dependent resistance associated with electron–phonon scattering in metals. A derivation of isotropic, unpolarized elementary radiators from anisotropic dipole radiation is presented in the Appendix.