题目

某工厂要修建一座烟囱.经勘测,打算建烟囱的地方的地面所能承受的最大压强是9.2×104Pa.设计的烟囱基础占地面积为4m2 , 建成后的烟囱约为41.7吨,取g=10N/㎏.问: (1) 该烟囱的重力是多少? (2) 该烟囱能否按原计划修建?如果不行,请大致说出可以采取什么措施? 答案:解:该烟囱的重力: G=mg=41.7×103kg×10N/kg=4.17×105N 解:烟囱对地面的压力: F=G=4.17×105N,烟囱对地面的压强:p= {#mathml#}FS{#/mathml#} = {#mathml#}4.17×105N4m2{#/mathml#} =1.04×105Pa,因p>9.2×104Pa, 所以,不能按原计划修建烟囱,采取的措施:可增大烟囱基础的占地面积来减小压强11.It was a busy morning,about 8:30,when an elderly gentleman in his 80s came to the hospital.I heard him saying to the nurse that he was in a hurry for all appointment(约会)at 9:30.   The nurse had him take a(36)seatin the waiting area,(37)tellinghim it would be at least 40minutes(38)beforesomeone would be able to see him.I saw him(39)lookingathis watch and decided,since I was (40)not busy-my patient didn't(41)turnupat the appointed hour,I would examine his wound.While taking care of his wound,I asked him if he had another doctor's appointment.  The gentleman said no and told me that he(42)neededto go to the nursing home to eat breakfast with his(43)wife.He told me that she had been (44)therefor a while and that she had a special disease.I asked if she would be (45)worriedif he was a bit late.He replied that she (46)nolongerknew who he was,that she had not been able to(47)recognizehim for five years now.I was(48)surprised,surprisedand asked him,"And you(49)stillgo every morning,even though she doesn't know who you are?"   He smiled and said,"She doesn't know me,but I know who she is."I had to hold back(50)tears as he left.   Now I(51)realizethat in marriages,true love is(52)acceptanceof all that is.The happiest people don't (53)necessarilyhave the best of everything; they just(54)makethe best of everything they have.(55)Lifeisn't about how to live through the storm,but how to dance in the rain.36.A.breathB.testC.seatD.break37.A.persuadingB.promisingC.understandingD.telling38.A.ifB.beforeC.sinceD.after39.A.taking offB.fixingC.looking atD.winding40.A.veryB.alsoC.seldomD.not41.A.turn upB.show offC.come onD.go away42.A.neededB.forgotC.agreedD.happened43.A.daughterB.wifeC.motherD.sister44.A.lateB.wellC.aroundD.there45.A.lonelyB.worriedC.doubtfulD.hungry46.A.so farB.neitherC.no longerD.already47.A.recognizeB.answerC.believeD.expect48.A.movedB.disappointedC.surprisedD.satisfied49.A.onlyB.thenC.thusD.still50.A.curiosityB.tearsC.wordsD.judgment51.A.realizeB.suggestC.hopeD.prove52.A.agreementB.expressionC.acceptanceD.exhibition53.A.necessarilyB.completelyC.naturallyD.frequently54.A.learnB.makeC.favorD.try55.A.AdventureB.BeautyC.TrustD.Life.
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