Ill -49 



ATTENUATION 

 (db/inch) 



8 10 12 14 16 18 



FREQUENCY ( kc ) 



FIGURE in-19 THEORETICAL AND OBSERVED ATTENUA- 



TIONS (AFTER LAIRD AND KENDIG) 



n(R) (cm--*) 



fr (kc) 

 16 1210 8 6 4 



nrn — \ \ — 



6U(R)=^nR'n(R) 

 (cm-i) 



FIGURE III- 20 DISTRIBUTION OF THE NUMBER OF BUBBLES 



AND FRACTIONAL VOLUME AS A FUNCTION 

 OF BUBBLE RADIUS (AFTER LAIRD AND 

 KENDIG) 



S-7001-0307 



