Concept explainers
Pressure of a Plucked String If a string with a fundamental frequency of 110 Hz is plucked in the middle, it will vibrate at the odd harmonics of 110. 330. 550,... Hz but not at the even harmonics of 220, 440, 660,... Hz. The resulting pressure P caused by the string is graphed below and can be modeled by the following equation.
(Source: Benade, A., Fundamentals of Musical Acoustics. Dover Publications. Roederer, J., Introduction to the Physics and Psychophysics of Music. Second Edition. Springer-Verlag.)
(a) Duplicate the graph shown here.
(b) Describe the shape of the sound wave that is produced.
(c) At lower frequencies, the inner ear will hear a tone only when the eardrum is moving outward. This occurs when P is negative. Determine the times over the interval [0.0.03 ] when this will occur.
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Trigonometry, Books a la Carte Edition (11th Edition)
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