Question

To practice Problem-Solving Strategy 16.1 Sound Intensity. A rescue team is searching for Andrew, a geologist who was stranded while conducting research in the mountains of Colorado. The team uses electronic listening devices in order to detect any shouts for help. The sound waves from his shouts reaching the base camp can be approximated by a sinusoidal wave with a frequency f = "520" Hz and displacement amplitude A = 4.50×10−8 m , where the sound wave properties are valid at the base camp where the measurements are being made. What sound intensity level will the rescue team measure from the frightened researcher? Assume the speed of sound is v=333m/s and the density of air rho = 1.28 kg/m3 .

Answer 1

Step-by-step explanation:

Intensity of wave is

2 π² f²A²v p

= 2 π² (520)² (4.5 ×10∧-8)² (333) (1.28)

I= 4.607 × 10∧-6

Intensity level is

β = 10 dB ㏒ (I÷Io)

=10 dB ㏒ (4.607 × 10∧-6 ÷ 10∧-12)

β = 66.6 dB

Bulk modulus is

B = v² p

= (333)² (1.28)

= 1.419 ×10∧5 Pa