THE SCIENCE AND APPLICATIONS OF ACOUSTICS - H. H. Arnold ...

Problems for Chapter 7 149ReferencesBeranek, Leo L. 1986. Acoustics. New York: American Institute of Physics, Chapters 5and 6.Beranek, Leo L. 1949. Acoustic Measurements. New York: John Wiley & Sons, pp. 317–321.Fletcher, Neville H. and Rossing, Thomas D. 1991. The Physics of Musical Instruments,1 st ed. New York: Spring-Verlag, pp. 150–155.Kinsler, Lawrence E. and Frey, Austin R. 1962. Fundamentals of Acoustics, 2nd ed. NewYork: John Wiley & Sons, Chapter 8. (Many users consider this edition to be the bestof the four issued to date.)Kinsler, Lawrence E., Frey, Austin R., Coppens, Alan B., and Sanders, James V. 1982.Fundamentals of Acoustics, 3rd ed. New York: John Wiley & Sons, Chapters 9 and 10.Olson, Harry F. 1967. Music, Physics and Engineering, 2nd ed. New York: Dover Publications,Chapter 4.Wood, Alexander. 1960. Acoustics. New York: Dover Publications, pp. 103–110.Problems for Chapter 71. Determine the minimum length of a pipe in which the input mechanical reactanceis equal to the input mechanical resistance for the frequency of 700 Hz.Assume the loading impedance is four times the pipe’s characteristic mechanicalimpedance ρ 0 cA.2. A condenser microphone is constructed by stretching a diaphragm across oneend of a hollow cylinder with a diameter of 2 cm and length of 0.75 cm. Theother end of the cylinder is open. Determine the ratio of the pressure at thediaphragm (considered to be a rigid plane) to the pressure at the open end asa function of frequency from 64 Hz to 2 kHz.3. A pipe is 1.2 m long and has a radius of 6 cm. It is being driven at one endby a piston (negligible mass). The other open end of the pipe terminates in aflange.(a) Find the fundamental resonance of the system.(b) If the piston has a displacement of 1 cm when being driven at 500 Hz,what is the amount of acoustic power being transmitted by plane wavestraveling to the open end of the pipe?(c) What is the acoustic power (in watts) being radiated out at the open endof the pipe?4. Consider a pipe that is 1.2 m long with a radius of 6 cm. It is being driven atone end by a piston of 0.02 kg mass and the same radius as the pipe. The otherend of the pipe terminates in an infinite baffle.(a) For 200 Hz frequency, find the mechanical impedance of the piston of thepipe, inclusive of the loading effect of the air inside the pipe.(b) For the above frequency, determine the amplitude of the force necessaryto drive the piston with a displacement amplitude of 0.50 cm.