Acoustics | Definition, Physics, & Facts

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acoustics</a></div><div class="ml-40 toc-drawer sub-toc-drawer"><ul class="list-unstyled" data-level="h2"><li data-target="#ref64052"><a class="w-100 link-gray-900" href="/science/acoustics/Reverberation-time">Reverberation time</a></li></ul><ul class="list-unstyled" data-level="h2"><li data-target="#ref64053"><a class="w-100 link-gray-900" href="/science/acoustics/Acoustic-criteria">Acoustic criteria</a></li></ul><ul class="list-unstyled" data-level="h2"><li data-target="#ref64054"><a class="w-100 link-gray-900" href="/science/acoustics/Acoustic-problems">Acoustic problems</a></li></ul></div></li></ul> <a class="toc-extra-link link-gray-900" href="https://www.britannica.com/science/acoustics/additional-info">References & Edit History</a> <a class="toc-extra-link link-gray-900" href="/facts/acoustics">Related Topics</a> </div> <div class="tlr-media-slider pb-10 mb-30"> <a class="section-header link-gray-900 font-serif font-14 font-weight-bold mb-10 mx-10" 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Berg</div> <div class="editor-description font-12 font-serif mt-5 clamp-description text-black">Supervisor, Teaching Support Services; Director, Lecture-Demonstration Facility, Department of Physics, University of Maryland, College Park. Coauthor of <em>The Physics of Sound.</em></div> </a> <div data-popper-arrow></div> </div> <span class="btn btn-link editor-link p-0 qa-byline-link gtm-byline font-12 byline-contributor text-decoration-underline"> Richard E. 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They write new content and verify and edit content received from contributors.</div> </a> <div data-popper-arrow></div> </div> <span class="btn btn-link editor-link p-0 qa-byline-link font-12 "> The Editors of Encyclopaedia Britannica</span></div> <div class="last-updated font-12 font-serif"> <a class="byline-edit-history" href="https://www.britannica.com/science/acoustics/additional-info#history" rel="nofollow">Article History</a> </div></div> </div> <button class="d-flex d-lg-none btn btn-outline-blue border rounded-sm shadow-sm mobile-toc-button gtm-mobile-toc-inline-button d-none d-sm-block js-sections-inline-button module-spacing btn d-lg-none"> <em class="material-icons mr-5 ml-n10 my-n5 md-icon" data-icon="toc"></em> Table of Contents </button> <div class="d-flex d-sm-none flex-row"> <button class="d-flex d-lg-none btn btn-outline-blue border rounded-sm shadow-sm mobile-toc-button gtm-mobile-toc-inline-button js-sections-inline-button module-spacing"> <em class="material-icons mr-5 ml-n10 my-n5 md-icon" data-icon="toc"></em> Table of Contents </button> <button class="ai-ask-button btn border-2 ai-ask-button btn border-2 module-spacing btn-sm js-inline-ai-ask-button btn-outline-red-400 border-red-400 p-10 ml-5"> Ask the Chatbot a Question </button> </div> <div class="js-qf-module qf-module px-40 px-sm-20 py-15 mx-auto module-spacing font-14 bg-gray-50 rounded"> <div class="facts-list mt-10"> <div class=""> <div class="js-fact mb-10 line-clamp clamp-3"> <dl> <dt>Key People: </dt> <dd><a href="/biography/John-William-Strutt-3rd-Baron-Rayleigh" topicid="492464">Lord Rayleigh</a></dd> <dd><a href="/biography/Sophie-Germain" topicid="230626">Sophie Germain</a></dd> <dd><a href="/biography/Archytas-of-Tarentum" topicid="33072">Archytas of Tarentum</a></dd> <dd><a href="/biography/Victor-Charles-Mahillon" topicid="358195">Victor-Charles Mahillon</a></dd> <dd><a href="/biography/Eric-Zepler" topicid="2068730">Eric Zepler</a></dd> </dl> <button class="js-more-btn d-none btn btn-unstyled font-12 bg-gray-50" aria-label="Toggle more/less fact data"> <em class="js-content link-blue">(Show more)</em> </button> </div> </div> <div class=""> <div class="js-fact mb-10 line-clamp clamp-3"> <dl> <dt>Related Topics: </dt> <dd><a href="/science/sound-physics" topicid="555255">sound</a></dd> <dd><a href="/science/physics-science" topicid="458757">physics</a></dd> <dd><a href="/science/architectural-acoustics" topicid="32864">architectural acoustics</a></dd> </dl> <button class="js-more-btn d-none btn btn-unstyled font-12 bg-gray-50" aria-label="Toggle more/less fact data"> <em class="js-content link-blue">(Show more)</em> </button> </div> <div class="text-center"> <a class="btn btn-sm btn-link p-0" href="/facts/acoustics"> See all related content </a> </div> </div> </div> </div><span class="marker before-article"></span><section data-level="1" id="ref1"><span class="marker PREMOD1 mod-inline"></span><p class="topic-paragraph"><strong><span id="ref530355"></span>acoustics</strong>, the <a href="https://www.britannica.com/science/science" class="md-crosslink autoxref " data-show-preview="true">science</a> concerned with the production, control, <a class="md-dictionary-link md-dictionary-tt-off eb" data-term="transmission" href="https://www.britannica.com/dictionary/transmission" data-type="EB">transmission</a>, reception, and effects of <a href="https://www.britannica.com/science/sound-physics" class="md-crosslink autoxref " data-show-preview="true">sound</a>. The term is derived from the Greek <em>akoustos</em>, meaning “heard.”</p><span class="marker MOD1 mod-inline"></span><span class="marker PREMOD2 mod-inline"></span><p class="topic-paragraph">Beginning with its origins in the study of mechanical vibrations and the radiation of these vibrations through mechanical waves, acoustics has had important applications in almost every area of life. It has been fundamental to many developments in the arts—some of which, especially in the area of musical scales and instruments, took place after long experimentation by artists and were only much later explained as theory by scientists. For example, much of what is now known about <a href="https://www.britannica.com/science/architectural-acoustics" class="md-crosslink autoxref " data-show-preview="true">architectural acoustics</a> was actually learned by trial and error over centuries of experience and was only recently formalized into a science.</p><span class="marker MOD2 mod-inline"></span><span class="marker PREMOD3 mod-inline"></span><p class="topic-paragraph">Other applications of <a class="md-dictionary-link md-dictionary-tt-off eb" data-term="acoustic" href="https://www.britannica.com/dictionary/acoustic" data-type="EB">acoustic</a> technology are in the study of geologic, atmospheric, and underwater phenomena. <span id="ref527537"></span><a href="https://www.britannica.com/science/psychoacoustics" class="md-crosslink ">Psychoacoustics</a>, the study of the physical effects of sound on biological systems, has been of interest since <a href="https://www.britannica.com/biography/Pythagoras" class="md-crosslink autoxref " data-show-preview="true">Pythagoras</a> first heard the sounds of vibrating strings and of hammers hitting anvils in the 6th century <span class="text-smallcaps">bc</span>, but the application of modern ultrasonic technology has only recently provided some of the most exciting developments in medicine. Even today, research continues into many aspects of the fundamental physical processes involved in waves and sound and into possible applications of these processes in modern life.</p><div class="one-good-fact-module"> </div><span class="marker MOD3 mod-inline"></span><span class="marker PREMOD4 mod-inline"></span><p class="topic-paragraph">Sound waves follow physical principles that can be applied to the study of all waves; these principles are discussed thoroughly in the article <a href="https://www.britannica.com/science/mechanics" class="md-crosslink " data-show-preview="true">mechanics of solids</a>. The article <a href="https://www.britannica.com/science/senses" class="md-crosslink " data-show-preview="true">ear</a> explains in detail the physiological process of hearing—that is, receiving certain <a href="https://www.britannica.com/science/wave-physics" class="md-crosslink autoxref " data-show-preview="true">wave</a> <a class="md-dictionary-link md-dictionary-tt-off eb" data-term="vibrations" href="https://www.britannica.com/dictionary/vibrations" data-type="EB">vibrations</a> and interpreting them as sound.</p><span class="marker MOD4 mod-inline"></span></section> <span class="marker end-of-content"></span><span class="marker after-article"></span></div> <div id="chatbot-root"></div> </div> </div> </div> <div class="ai-dialog-placeholder"></div> </div> </div> <aside class="col-md-da-320"></aside> </div> </div> </div> </div> </article></div> </div></div> </div> </main> <div id="md-footer"></div> <noscript><iframe src="//www.googletagmanager.com/ns.html?id=GTM-5W6NC8" height="0" width="0" style="display:none;visibility:hidden"></iframe></noscript> <script type="text/javascript" id="_informizely_script_tag"> var IzWidget = IzWidget || {}; (function (d) { var scriptElement = d.createElement('script'); scriptElement.type = 'text/javascript'; scriptElement.async = true; scriptElement.src = "https://insitez.blob.core.windows.net/site/f780f33e-a610-4ac2-af81-3eb184037547.js"; var node = d.getElementById('_informizely_script_tag'); node.parentNode.insertBefore(scriptElement, node); } )(document); </script>  <script> window.ap3c = window.ap3c || {}; var ap3c = window.ap3c; ap3c.cmd = ap3c.cmd || []; ap3c.cmd.push(function() { ap3c.init('ZO4siT4cLwnykPnzZWJtd3Byb2Q', 'https://engage.email.britannica.com/'); ap3c.track({v: 0}); }); ap3c.activity = function(act) { ap3c.act = (ap3c.act || []); ap3c.act.push(act); }; var s, t; s = document.createElement('script'); s.type = 'text/javascript'; s.src = "https://engage.email.britannica.com/app.js"; t = document.getElementsByTagName('script')[0]; t.parentNode.insertBefore(s, t); </script> <script class="marketing-page-info" type="application/json"> {"pageType":"Topic","templateName":"DESKTOP","pageNumber":1,"pagesTotal":8,"pageId":4044,"pageLength":303,"initialLoad":true,"lastPageOfScroll":false} </script> <script class="marketing-content-info" type="application/json"> [] </script> <script src="https://cdn.britannica.com/mendel-resources/3-130/js/libs/jquery-3.5.0.min.js?v=3.130.14"></script> <script type="text/javascript" data-type="Init Mendel Code Splitting"> (function() { $.ajax({ dataType: 'script', cache: true, url: 'https://cdn.britannica.com/mendel-resources/3-130/dist/topic-page.js?v=3.130.14' }); })(); </script> <script class="analytics-metadata" type="application/json"> {"leg":"D","adLeg":"D","userType":"ANONYMOUS","pageType":"Topic","pageSubtype":null,"articleTemplateType":"PAGINATED","gisted":false,"pageNumber":1,"hasSummarizeButton":false,"hasAskButton":false} </script> <script type="text/javascript"> EBStat={accountId:-1,hostnameOverride:'webstats.eb.com',domain:'www.britannica.com', json:''}; </script> <script type="text/javascript"> ( function() { $.ajax( { dataType: 'script', cache: true, url: '//www.britannica.com/webstats/mendelstats.js?v=1' } ) .done( function() { try {writeStat(null,EBStat);} catch(err){} } ); })(); </script> <div id="bc-fixed-dialogue"></div> </body> </html>

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Acoustics | Definition, Physics, & Facts | Britannica