If one is not familiar with the physics of the violin, it is not easy to guess, even for an experimental physicist, that the so-called Helmholtz motion can be obtained as a solution to the ...one-dimensional wave equation for the motion of a bowed violin string. It is worth visualising this aspect from a graphical perspective without recourse to ordinary Fourier analysis, as has customarily been done. We show in this paper how to obtain the shape of the Helmholtz trajectory, that is, two mirror-symmetric parabolas, in the ideal case of no losses from internal dissipation and no viscous drag from the air and the non-rigid end supports. We also show that the velocity profile of the Helmholtz motion is also a solution of the one-dimensional wave equation. Finally, we again derive the parabolic shape of the Helmholtz trajectory by applying the principle of energy conservation to a violin string.
A bow with horse tail hair is used to play the violin. New and worn-out bow hairs were observed by atomic force microscopy. The cuticles of the new bow hair were already damaged by bleach and ...delipidation, however the worn-out bow hairs were much more damaged and broken off by force, which relates to wearing out.
On Transient Motion of a Bowed String NAKAI, Mikio; MURAKAMI, Masao
Transactions of the Japan Society of Mechanical Engineers Series C,
2001/10/25, Volume:
67, Issue:
662
Journal Article
Open access
The transient behavior of a bowed string from a Helmholtz motion to a double slip motion was observed using a simple apparatus consisting of nylon lines which served as a bow, and a string. As the ...bow speed increases, the motion transits from a Helmholtz motion to a double slip motion. Two Helmholtzian waves with different amplitudes and phases occur during the transition from a Helmholtz motion to a perfect double slip motion. This behavior is examined using numerical simulations, which provide good agreement with the experiments.
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