580 Heat and the First Law of Thermodynamics*P20.6The laser energy output:P∆t=××=×−1 60 104 00 101394..J s 2.50 10sJej.The teakettle input:QmcT==⋅°°=×∆0800268 105kg 4 186 J kg C 80 CJbg.This is larger by 6.70 times.P20.7QQcoldhot=−mc Tmc TTTTfff∆∆afdibgwaterironkgJ kg CCkgJ kg CCC⋅°−°= −⋅°−°=°20 0418625 01 5044860029 6..P20.8Let us find the energy transferred in one minute.Qmc m cTQ=+=⋅°+⋅°−°=−cup cupwater waterkgJ kg CkgJ kg CCJ∆0 2009000 8001 505 290.bgbgIf this much energy is removed from the system each minute, the rate of removal is==Qt∆529088 288 2J60.0 sJsW.P20.9(a)coldhotmc mcTT mcTT mc TTw wc cfcfunk unk
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This note was uploaded on 12/14/2011 for the course PHY 203 taught by Professor Staff during the Fall '11 term at Indiana State University .