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Suppose a vibrating tuning fork compresses air molecules.And for this it has to do work.As compression occurs,its temperature increases.Does the energy spent by the fork go as the increased internal energy of the molecules?If so,then which energy goes as sound energy?As the process is adiabatic,does this given energy always remain inside the air particles even when it is expanded or is it used to compress another layer to make forward the disturbance-energy to our ear as sound? In a word,the main query is what happens to the energy given out by the vibrating fork:does it become sound or the heat of the compressed layer or both?

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marked as duplicate by Brandon Enright, Kyle Kanos, Emilio Pisanty, Qmechanic Feb 17 '14 at 20:20

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

I updated my previous answer with several links to academic websites explaining, in detail, how the heat is generated via full thermodynamic constitutive relations for gases. –  DumpsterDoofus Feb 17 '14 at 16:55
Ur explanation & the links were quite good...albeit this question is related to my previous questions,they are not duplicate. –  user36790 Feb 19 '14 at 8:50

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Propagating sound is the periodic motion of the molecules passed on through the air. So the kinetic energy of the molecules is also passed on. Temperature is merely a measure of the mean kinetic energy of all the molecules in a gas. So temperature rises only locally where the potential energy decreases, because the distance between the molecules decreases. Half a wavelength further the distance between the molecules increases, potential energy increases and the temperature will fall. So to answer the question, the energy of the vibrating fork is converted into sound

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thank u very much for ur explanation but i want to know how can i relate it to the adiabatic process?Does the particles undergo SHM? –  user36790 Feb 17 '14 at 16:41
Read the answers to your other question. This question never mentions adiabatic process nor isotherm. –  KvdLingen Feb 17 '14 at 21:49

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