Halliday 2 Cap 18 - P18 019

Transcript

19. The intensity is given by I = 12 ρvω 2 s2m , where ρ is the density of air, v is the speed of sound in air, ω is the angular frequency, and sm is the displacement amplitude for the sound wave. Replace ω with 2πf and solve for sm :

2 I 1.00 × 10−6 W/m = = 3.68 × 10−8 m . sm = 3 2π 2 ρvf 2 2π 2 (1.21 kg/m )(343 m/s)(300 Hz)2