A Sound Source Emits 20

question 45

Multiple Choice

A sound source emits 20.0 W of acoustical power spread equally in all directions. The threshold of hearing is 1.0 × 10^-12 W/m². What is the sound intensity level 30.0 m from the source?

• A) 92.5 dB
• B) 81.5 dB
• C) 1.77 × 10^-3 dB
• D) 1.77 × 10^-3 W
• E) -27.5 dB

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