{"id":3738,"date":"2023-01-09T10:25:47","date_gmt":"2023-01-09T10:25:47","guid":{"rendered":"https:\/\/9thclass.deltapublications.in\/?page_id=3738"},"modified":"2025-12-19T09:04:42","modified_gmt":"2025-12-19T09:04:42","slug":"s-12-d-propagation-of-sound","status":"publish","type":"page","link":"https:\/\/9thclass.deltapublications.in\/index.php\/s-12-d-propagation-of-sound\/","title":{"rendered":"S-12.d Propagation Of Sound"},"content":{"rendered":"\n<h2 class=\"wp-block-heading has-text-align-center has-text-color\" style=\"color:#00056d;text-transform:uppercase\"><strong>Propagation Of Sound<\/strong><\/h2>\n\n\n\n<p class=\"has-text-color has-huge-font-size\" style=\"color:#74008b\"><strong>Key Notes:<\/strong><\/p>\n\n\n\n<figure class=\"wp-block-image is-resized\"><img decoding=\"async\" src=\"https:\/\/media.sciencephoto.com\/c0\/50\/87\/58\/c0508758-800px-wm.jpg?utm_source=chatgpt.com\" alt=\"https:\/\/media.sciencephoto.com\/c0\/50\/87\/58\/c0508758-800px-wm.jpg?utm_source=chatgpt.com\" style=\"width:435px;height:auto\"\/><\/figure>\n\n\n\n<figure class=\"wp-block-image is-resized\"><img decoding=\"async\" src=\"https:\/\/d2cvjmix0699s1.cloudfront.net\/resources\/elephango\/_userimages\/sound-wave-diagram-11474.jpg?utm_source=chatgpt.com\" alt=\"https:\/\/d2cvjmix0699s1.cloudfront.net\/resources\/elephango\/_userimages\/sound-wave-diagram-11474.jpg?utm_source=chatgpt.com\" style=\"width:447px;height:auto\"\/><\/figure>\n\n\n\n<figure class=\"wp-block-image is-resized\"><img decoding=\"async\" src=\"https:\/\/images.openai.com\/thumbnails\/url\/7yELJnicu5meUVJSUGylr5-al1xUWVCSmqJbkpRnoJdeXJJYkpmsl5yfq5-Zm5ieWmxfaAuUsXL0S7F0Tw4Md8usCCw388gPq6wyTjf2Kg_OLPYqCvL1SM0wDg6qrMrKqghy8w8yNnBxVCu2NTQAAB_7JVQ?utm_source=chatgpt.com\" alt=\"https:\/\/hyperphysics.phy-astr.gsu.edu\/hbase\/Sound\/imgsou\/lwav2.gif?utm_source=chatgpt.com\" style=\"width:434px;height:auto\"\/><\/figure>\n\n\n\n<h3 class=\"wp-block-heading has-large-font-size\">\ud83d\udccc <strong>What is Sound?<\/strong><\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Sound is a <strong>form of energy<\/strong> that produces the <strong>sensation of hearing<\/strong>.<\/li>\n\n\n\n<li>It is produced due to the <strong>vibrations<\/strong> of objects.<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading has-large-font-size\">\ud83d\udccc <strong>How Does Sound Travel?<\/strong><\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Sound travels in the form of <strong>waves<\/strong>.<\/li>\n\n\n\n<li>It moves through a <strong>medium<\/strong> (solid, liquid, or gas).<\/li>\n\n\n\n<li>Sound <strong>cannot travel in a vacuum<\/strong> \ud83d\udeab.<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading has-large-font-size\">\ud83d\udccc <strong>Type of Sound Wave<\/strong><\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Sound waves are <strong>longitudinal waves<\/strong>.<\/li>\n\n\n\n<li>Particles of the medium vibrate <strong>back and forth<\/strong> in the <strong>same direction<\/strong> as the wave travels.<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading has-large-font-size\">\ud83d\udccc <strong>Compression and Rarefaction<\/strong><\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Compression (C):<\/strong>\n<ul class=\"wp-block-list\">\n<li>Region where particles are <strong>closer together<\/strong>.<\/li>\n\n\n\n<li>High pressure and high density.<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Rarefaction (R):<\/strong>\n<ul class=\"wp-block-list\">\n<li>Region where particles are <strong>far apart<\/strong>.<\/li>\n\n\n\n<li>Low pressure and low density.<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li>A sound wave consists of <strong>alternate compressions and rarefactions<\/strong>.<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading has-large-font-size\">\ud83d\udccc <strong>Medium Required for Propagation<\/strong><\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Sound can travel through:\n<ul class=\"wp-block-list\">\n<li><strong>Solids<\/strong> (fastest) \ud83e\udea8<\/li>\n\n\n\n<li><strong>Liquids<\/strong><\/li>\n\n\n\n<li><strong>Gases<\/strong> (slowest)<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li>Speed of sound depends on the <strong>nature of the medium<\/strong>.<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading has-large-font-size\">\ud83d\udccc <strong>Speed of Sound<\/strong><\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Speed of sound in air at room temperature \u2248 <strong>343 m\/s<\/strong>.<\/li>\n\n\n\n<li>Sound travels:\n<ul class=\"wp-block-list\">\n<li><strong>Fastest in solids<\/strong><\/li>\n\n\n\n<li><strong>Slower in liquids<\/strong><\/li>\n\n\n\n<li><strong>Slowest in gases<\/strong><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading has-large-font-size\">\ud83d\udccc <strong>Sound Energy Transfer<\/strong><\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Sound transfers <strong>energy<\/strong>, not matter.<\/li>\n\n\n\n<li>Particles only <strong>vibrate<\/strong> around their mean positions.<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading has-large-font-size\">\ud83d\udccc <strong>Example of Sound Propagation<\/strong><\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>When a bell rings \ud83d\udd14:\n<ul class=\"wp-block-list\">\n<li>Bell vibrates \u2192 air particles vibrate \u2192 vibrations reach our ears \u2192 sound is heard.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading has-large-font-size\">\ud83d\udccc <strong>Important Points to Remember<\/strong><\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Sound needs a <strong>material medium<\/strong>.<\/li>\n\n\n\n<li>Sound waves are <strong>mechanical waves<\/strong>.<\/li>\n\n\n\n<li>No sound is heard in <strong>outer space<\/strong> \ud83d\ude80.<\/li>\n<\/ul>\n\n\n\n<div class=\"wp-block-group has-large-font-size\"><div class=\"wp-block-group__inner-container is-layout-constrained wp-block-group-is-layout-constrained\">\n<p class=\"has-text-color has-large-font-size\" style=\"color:#d90000\">Let&#8217;s practice!<\/p>\n<\/div><\/div>\n\n\n\n<div class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-9d6595d7 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<figure class=\"wp-block-image size-full\"><a href=\"https:\/\/wordwall.net\/play\/82474\/595\/783\"><img loading=\"lazy\" decoding=\"async\" width=\"500\" height=\"500\" src=\"https:\/\/9thclass.deltapublications.in\/wp-content\/uploads\/2023\/03\/Worksheet-1-2-55.png\" alt=\"\" class=\"wp-image-6505\" srcset=\"https:\/\/9thclass.deltapublications.in\/wp-content\/uploads\/2023\/03\/Worksheet-1-2-55.png 500w, https:\/\/9thclass.deltapublications.in\/wp-content\/uploads\/2023\/03\/Worksheet-1-2-55-300x300.png 300w, https:\/\/9thclass.deltapublications.in\/wp-content\/uploads\/2023\/03\/Worksheet-1-2-55-150x150.png 150w\" sizes=\"auto, (max-width: 500px) 100vw, 500px\" \/><\/a><\/figure>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<figure class=\"wp-block-image size-full\"><a href=\"https:\/\/wordwall.net\/play\/81561\/673\/176\"><img loading=\"lazy\" decoding=\"async\" width=\"500\" height=\"500\" src=\"https:\/\/9thclass.deltapublications.in\/wp-content\/uploads\/2023\/03\/Worksheet-1-1-1-58.png\" alt=\"\" class=\"wp-image-6506\" srcset=\"https:\/\/9thclass.deltapublications.in\/wp-content\/uploads\/2023\/03\/Worksheet-1-1-1-58.png 500w, https:\/\/9thclass.deltapublications.in\/wp-content\/uploads\/2023\/03\/Worksheet-1-1-1-58-300x300.png 300w, https:\/\/9thclass.deltapublications.in\/wp-content\/uploads\/2023\/03\/Worksheet-1-1-1-58-150x150.png 150w\" sizes=\"auto, (max-width: 500px) 100vw, 500px\" \/><\/a><\/figure>\n<\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>Propagation Of Sound Key Notes: \ud83d\udccc What is Sound? \ud83d\udccc How Does Sound Travel? \ud83d\udccc Type of Sound Wave \ud83d\udccc Compression and Rarefaction \ud83d\udccc Medium Required for Propagation \ud83d\udccc Speed of Sound \ud83d\udccc Sound Energy Transfer \ud83d\udccc Example of Sound Propagation \ud83d\udccc Important Points to Remember Let&#8217;s practice!<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"om_disable_all_campaigns":false,"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"footnotes":""},"class_list":["post-3738","page","type-page","status-publish","hentry","entry"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/9thclass.deltapublications.in\/index.php\/wp-json\/wp\/v2\/pages\/3738","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/9thclass.deltapublications.in\/index.php\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/9thclass.deltapublications.in\/index.php\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/9thclass.deltapublications.in\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/9thclass.deltapublications.in\/index.php\/wp-json\/wp\/v2\/comments?post=3738"}],"version-history":[{"count":13,"href":"https:\/\/9thclass.deltapublications.in\/index.php\/wp-json\/wp\/v2\/pages\/3738\/revisions"}],"predecessor-version":[{"id":18333,"href":"https:\/\/9thclass.deltapublications.in\/index.php\/wp-json\/wp\/v2\/pages\/3738\/revisions\/18333"}],"wp:attachment":[{"href":"https:\/\/9thclass.deltapublications.in\/index.php\/wp-json\/wp\/v2\/media?parent=3738"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}