We show how a single metal guitar string of fixed length can produce a musical scale. The string is placed near a permanent magnet, and by applying an AC to the string at the frequency of the desired musical note, the Lorentz force creates vibrations in the string at that frequency. The tension of the string is set so that its harmonics correspond to the desired notes. A one-octave scale can be approximated by using these harmonic frequencies, allowing several melodies to be played using our non-contact monochord. This project could be adopted for demonstration or laboratory projects.

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