Experimental Measurement of the Diameter of a Human Hair via Two-Color Light Diffraction.

The width of a human hair sourced from a female elementary school student was measured by light diffraction using red and blue laser pointers. The two laser sources both provided consistent estimates of the hair diameter of approximately 50 µm. The overall experiment and writing process provided a temporary respite from COVID-19 shelter-in-place requirements and deteriorating spring weather that precluded outdoor activities.