SOBRE A NÃO-LINEARIDADE DE FENÔMENOS ACÚSTICOS E O FUNCIONAMENTO DA FLAUTA TRANSVERSA: UMA INCURSÃO PELA ACÚSTICA MUSICAL.

Sound production on musical instruments is a fundamental referent for the acoustics teaching in secondary and higher education. One main feature found amid established models for approaching acoustical phenomena in Physics is linearity. Indeed, researches in the field of musical acoustics indicates that most musical instruments involve fundamentally nonlinear processes without which one can not understand the operation of these instruments. In this paper, we contribute to the discussion of acoustical phenomena in teaching Physics, approaching the limits of the hypothesis of linearity in musical acoustics from a specific instrument: the transverse flute. We discuss the acoustic wave equation (the equation that governs the propagation of sound waves in fluids such as air), highlighting the assumptions that underpin this equation and its validity. In fact, the validity of acoustic wave equation is closely related to the question of linearity on acoustical phenomena. Finally, we discuss the technique of excitation of the transverse flute (embouchure) to find it an essential nonlinearity involved in producing sound with this instrument. We believe that this discussion is a contribution to the refinement of the established models in approaching acoustical phenomena in higher education. [ABSTRACT FROM AUTHOR]