5. You are investigating the power output of a speaker to ensure it is safe to use at an outdoor concert. You can treat the speaker as a point source generating spherically symmetric waves and you can assume the waves do not reflect off any nearby surfaces. a) When you are 7.5 m from the speaker, your ears encounter an intensity of 0.11 W/m². An intensity of 1 W/m² is often used as a threshold for pain. How much closer can you get to the speaker before your ears begin to hurt? b) On average, how much power is the speaker supplying? Using the average power, about how much energy does the speaker supply in 2 seconds? c) At the concert, you know that audience members are planned be 2 m closer to the speaker than how close you could get without experiencing pain (your answer to part a). You decide to decrease the power supplied by the speaker to ensure the closest audience members do not encounter pain. What should you adjust the power output of the speaker to be?

5. You are investigating the power output of a speaker to ensure it is safe to use at an outdoor concert. You can treat the speaker as a point source generating spherically symmetric waves and you can assume the waves do not reflect off any nearby surfaces. a) When you are 7.5 m from the speaker, your ears encounter an intensity of 0.11 W/m². An intensity of 1 W/m² is often used as a threshold for pain. How much closer can you get to the speaker before your ears begin to hurt? b) On average, how much power is the speaker supplying? Using the average power, about how much energy does the speaker supply in 2 seconds? c) At the concert, you know that audience members are planned be 2 m closer to the speaker than how close you could get without experiencing pain (your answer to part a). You decide to decrease the power supplied by the speaker to ensure the closest audience members do not encounter pain. What should you adjust the power output of the speaker to be?

Physics for Scientists and Engineers

10th Edition

ISBN:9781337553278

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter17: Superposition And Standing Waves

Section: Chapter Questions

Problem 6P: Two identical loudspeakers 10.0 m apart are driven by the same oscillator with a frequency of f =...

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