Simple practical activities are proposed for the characterization of the sound produced by guitars and electric guitars with a harmonic analysis. Among them, we propose a demonstration that can be carried out in real time at the classroom. In the developed activities, sound samples produced by string instruments are captured and analyzed within a spectral approach. Physical characteristics of the guitar strings are explored. Experimental results are compared with the theoretical predictions, with excellent agreement. The presented tools can be used as support material in the study of vibrating strings, oscillations, waves, differential equations, harmonic analyses based on Fourier transform, and physics laboratory instrumentation.
physics teaching; waves; harmonic analysis; wave equation