head 1.2; access; symbols; locks; strict; comment @# @; 1.2 date 2018.03.15.08.55.37; author root; state Exp; branches; next 1.1; 1.1 date 2018.03.15.07.46.45; author root; state Exp; branches; next ; desc @This document (4.2 A slinky spring) is re-created by black-wolf-cc on 01 August 2017 @ 1.2 log @This document (4.2 A slinky spring) is lastly updated by black-wolf-cc status:PUBLISHED on 15 March 2018 @ text @{ "_id": { "$oid": "59b7e5342c4796015b350d49" }, "_type": "GSystem", "access_policy": "PUBLIC", "altnames": "4.2 A slinky spring", "annotations": [], "attribute_set": [], "author_set": [], "collection_set": [], "comment_enabled": null, "content": "

Slinky spring

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We will try to see if a slinky spring could provide us clues about how sound travels. Consider a slinky spring kept on a table. We can compress it by giving it a sudden jerk from one side. 
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\r\nWatch the slow motion video given below.  You can also try it out in your classroom.
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                          Video 4.2 (a): A single compression traveling along a slinky
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\r\nNow let us move our hand back and forth.

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Video 4.2 (b): Many compressions and rarefactions traveling along a slinky

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\r\nYou can see that there are alternate regions where the slinky spring is compressed and where it is elongated. The diaphragm of a speaker also moves back and forth. It compresses the air when it moves forward and makes the air rarer/sparser/less dense when it moves back. Just as these successive compressions and rarefactions that travel along the slinky, sound travels away from a speaker through air. Sound travels in the same way through liquids and solids too.

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