<11Problem 14.92A machine shop has 120 equally noisy machinesthat together produce an intensity level of 92 dB.Part AIf the intensity level must be reduced to 88 dB, how many machines must be turned off?Express your answer as an integer.SubmitPrevious Answers Request AnswerX Incorrect; Try Again; 4 attempts remainingProvide FeedbackP PearsonCopyright © 2020 Pearson Education Inc. All rights reserved.| Terms of Use | Privacy Policy | Permissions | ContactMacBook Air80888DIIDDF3F4F5F6F7F8F9F10#3$&)4.78.ER.YPこの< CO

Given data The number of machines in the shop is n = 120. The intensity level produced by the machines is L = 92 dB. Let us consider the intensity produced by one machine I. Therefore, L=10log10nII092 dB=10log10120II09.2 dB=log10120II0120II0=109.2I=109.2120I0Now, let the intensity level of the N machines is L = 82 dB L=10log10NII08.8 dB=10log10NII08.8 dB=log10NII0NII0=108.8N=108.8×I0I On substituting I in the above equation as, N=108.8×I0109.2120I0N=108.8×120109.2N=48 Therefore, the machines that have to be turned off is calculated as, Net machines=n-NNet machines=120-48Net machines=72 Thus, the machines that have to be turned off is 72

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A machine shop has 120 equally noisy machines that together produce an intensity level of 92 dB. - Part A If the intensity level must be reduced to 88 dB, how many machines must be turned off Express your answer as an integer. ?

A machine shop has 120 equally noisy machines that together produce an intensity level of 92 dB. - Part A If the intensity level must be reduced to 88 dB, how many machines must be turned off Express your answer as an integer. ?

College Physics

11th Edition

ISBN:9781305952300

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter1: Units, Trigonometry. And Vectors

Section: Chapter Questions

Problem 1CQ: Estimate the order of magnitude of the length, in meters, of each of the following; (a) a mouse, (b)...

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