資源描述:
《heat and temperature熱與溫度》由會員上傳分享,免費(fèi)在線閱讀,更多相關(guān)內(nèi)容在應(yīng)用文檔-天天文庫。
1、UnitC-HeatandTemperatureSection1-Humanneedshaveledtotechnologiesforobtainingandcontrollingheat.Subsection1.1-HistoryofHeatTechnologiesHeatistheenergythatisgivenofffromthemovementoftinyparticlesthatmakeupallmatter.Heattechnologiesaretechnologiesthatuseandcontrolheatinawaythatmeetsourneedsan
2、dwants.Examplesincludefurnaces,fireplace,microwave,freezers,winterjackets.·Whataresomeexamplesoftechnologiesfromthepastandhowaretheydifferentfromtoday?Dependingonourculture,weusedifferenttypesofheattechnologiesandweusethemindifferentways.Theimportanceofheatislinkedtoallofourbasicneeds(air,
3、shelter,water,andfood).Canyouexplainhow?Iftherangeoftemperaturethatwecanexistatisbetween0°C-45°Cthenhowdowesurviveinthewinter?Subsection1.2-HeatTechnologiesinEverydayLifeStandardoflivingreferstohowmuchandwhatkindoftechnologyweusedaily.Themoretechnologythehigherourstandardoflivingbecomes.Ar
4、esourcethatdoesnotrunoutoranactivitythatwecancontinueforalongperiodoftimewithoutbadresultsissaidtobesustainable.Canyouthinkofsomeexamples?Section2-Heataffectsmatterindifferentways.Subsection2.1-StatesofMatterandTheParticleModelofMatterMatterisanythingthathasmassandtakesupspace.Itcanexistin
5、threestatesorforms:a)solidb)liquidc)gasHeatenergyisaformofenergy.Ittransfersfromhotterobjectstocoolerones.Forexample-puttingyourbarehandontheice.The"cold"doesn'tcomeintoyourhandtheheatenergyfromyourhandgoesintotheice.Theofficialunitofheatenergyisthejoule(J).ChangesofStateGASEvaporationCond
6、ensation(100°C)(100°C)thereareexceptionsLIQUIDthereareexceptionsMeltingFreezing(0°C)(0°C)SOLIDParticleModelofMatter1.Allmatterismadeupofextremelytinyparticles.2.Thetinyparticlesofmatterarealwaysmoving.3.Addingheattomattermakestheparticlesmovearoundfaster.4.Theparticleshavespacebetweenthem.
7、5.Thereareattractiveforcesbetweentheparticles.Astheparticlesgainheatenergytheybegintomovearoundfaster.Thespacesbetweentheparticlesgetlarger.Theattractiveforcesbetweentheparticlesbecomeweaker.Whenenergycausesmovementwecancallitkineticenergy.Soaddingheatincrease