At an outdoor music event, a dB meter records 130 dB when placed 2.25 m in front of a loudspeaker near the stage. A) What was the power output of the speaker, assuming uniform spherical spreading of the sound and neglecting any absorption, reflection and interference of the sound that may occur? B) How far away would you need to be for the sound level to be 80 dB?

At an outdoor music event, a dB meter records 130 dB when placed 2.25 m in front of a loudspeaker near the stage. A) What was the power output of the speaker, assuming uniform spherical spreading of the sound and neglecting any absorption, reflection and interference of the sound that may occur? B) How far away would you need to be for the sound level to be 80 dB?

University Physics Volume 1

18th Edition

ISBN:9781938168277

Author:William Moebs, Samuel J. Ling, Jeff Sanny

Publisher:William Moebs, Samuel J. Ling, Jeff Sanny

Chapter16: Waves

Section: Chapter Questions

Problem 77P: The low-frequency speaker of a stereo set has asurface area of A=0.05 m2 and produces 1 W of...

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