48 



MECHANICAL VIBRATING SYSTEMS 



cycles to 30,000 cycles. The frequency of open and closed pipes may be 

 computed from the above equations. The sound vibrations in the pipe 

 are set up by the stream of air which is controlled by the vibration in the 

 pipe. It is an oscillatory system fed by a direct current of air or gas. 



Table 3.1 young's modulus .9, in dynes per square cen- 

 timeter, POISSOn's ratio, <7 AND DENSITY p, IN GRAMS PER 

 CUBIC CENTIMETER 



