2019年12月大学英语六级阅读晨读美文:The-Source-of-Energy
摘要:2019年12月大学英语六级阅读晨读美文:TheSourceofEnergyTheSourceofEnergyAsummaryofthephysicalandchemicalnatureoflifemustbegin,notontheEarth,butintheSun;infact,attheSun'sverycenter.ItisherethatistobefoundthesourceoftheenergythattheSunconstantlypoursoutintospaceaslightandheat.ThisenergyisliberatedatthecenteroftheSunasbillionsuponbillionsofnucleiofhydrogenatomscollidewitheachotherandfusetogethertoformnucleiofhelium,andindoingso,releasesomeoftheenergythatisstoredinthenucleiofatoms.TheoutputoflightandheatoftheSunrequiresthatsome600milliontonsofhydrogenbeconvertedintoheliumintheSuneverysecond.ThistheSunhasbeendoingforseveralthousandsofmillionsofyears.ThenuclearenergyisreleasedattheSun'scenterashigh-ene
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