Whenpeoplethinkaboutstructures,theyoftenthinkabouttowersandbridges.
Whilethesestructuresareimpressive,thetruthisthateveryobjectyouencounterisastructure.
Ifyoupacksnowtomakeasnowball,youhavemadeastructure.
Ifyoucombineingredientsandbakealoafofbread,youhavealsomadeastructure.
Ifyoulookcarefullyatawidevarietyofstructures,youwillnoticethatmanyofthemhavesimilarities.
Differentstructuresmightservethesamefunction,likethestructuresinFigures4.
4and4.
5.
Inthissection,youwillexplorewaystoclassifystructures.
100UNITBStructures:FormandFunctionClassificationofStructures4.
1Hereisasummaryofwhatyouwilllearninthissection:Astructurecanbeclassifiedbyitsfunction.
Astructurecanbeclassifiedbyitsconstruction.
Astructurecanbeclassifiedasasolid,frame,orshellstructure.
B4StartingPointThinkaboutatleastsixdifferentstructuresthatyoucanuseasaseat.
Makealistofthem.
Somecanbeindoors,somecanbeoutdoors.
WhataretheadvantagesanddisadvantagesofeachoneinitsfunctionasaseatShareyourideaswithaclassmate.
HaveaSeatSkillsACFigure4.
5Acarseathasaspecificfunction.
Figure4.
4Arockcanserveasaseat.
sci7_ch04_3rd.
qxd7/15/085:15PMPage100ClassifyingStructuresWeoftenclassifystructuresbylookingattheirfunctions.
Somestructuresaremadetocontainsomething,somestructuressupportsomethingontop,andsomespanaspace.
Forexample,ifyounoticesoilrunningoutofyourschoolgardenwhenitrains,youmaydecidetobuildaretainingwalltoholdthesoilin.
Ifyouhavetroublereachingahighshelf,youmayuseasteporstooltoliftyourselfup.
Ifworkersarebuildingawall,theybuildscaffoldingfirst,andwalkaroundsafely(Figure4.
6).
Abridgeisastructuredesignedtospanagap.
Sometimesthegapisastreamorriver(Figures4.
7and4.
8).
Otherbridgesspananotherroadway;ifso,wecallthebridgeanoverpass.
Earlybridgesconsistedofalogfelledoverastream;modernbridgesaredesignedinmanydifferentforms.
Lookatthebridgesinyourcommunity.
Nomatterhowsimpleorcomplicatedtheformofeachbridge,itsfunctionisstilltospanagapsafely.
Anotherwaytosortstructuresistoexaminehowtheyarebuiltandwhattheyarebuiltfrom.
WewilllookatthisinChapter5.
Athirdwaytoclassifystructuresistodividethembytheirforms,intosolidstructures,framestructures,andshellstructures.
101Designersconsidertheformandthefunctionofastructureandtheforcesthatactonit.
Figure4.
6Constructionworkerserectascaffoldsothattheycanworkonhighwalls.
Figure4.
8Coveredbridgesweredesignedandbuiltmanyyearsago.
Theroofallowedthesnowtoslideoffsothatitsweightwouldnotdamagethebridge.
ThiscoveredbridgeinGuelphwasbuiltrecentlybyvolunteers.
Figure4.
7ThreebridgesinVancouver.
ThemodernbridgeinfrontistheSkyTrainBridge,themiddleoneisaroadbridge,andthelowestisarailwaybridge.
Therailwaybridgehasa"swing"sectionthatopenstoletshipsthrough.
B5DuringReadingGoodreadersactivatetheirpriorknowledgebymakingconnectionsbetweenwhattheyreadandthemselves,theworld,and/orothertexts.
Asyoureadaboutclassifyingstructuresinthissection,thinkaboutconnectionsyoucanmaketotheinformationpresented.
MakingConnectionssci7_ch04_3rd.
qxd7/15/085:15PMPage101SolidStructuresDoyouknowwhatmountains,dams,sandcastles,waxcandles,andappleshaveincommonAllareconsideredsolidstructures(Figure4.
9).
Mostsolidstructuresaresolidallthewaythrough,althoughamountainmightcontaincaves,adammighthaveroomstoholdelectricalgenerators,andanapplemayhaveawormhole.
Asolidstructureweighsmorethanahollowstructureofthesamesizeandmadeofthesamematerial.
102UNITBStructures:FormandFunctionB6LearningCheckpointDrawatablewithfourcolumnsandsixrows.
Inthefirstcolumn,writethenamesofsixstructuresyoucanseeinyourclassroom.
Asyouworkthroughthechapter,writethefunctionofeachstructureinColumn2.
Ifyouareunsureofthefunction,putaquestionmark.
InColumn3,listthematerialseachismadeof.
InColumn4,writewhetheryouthinkitisasolidstructure,aframestructure,orashellstructure.
Compareyourtablewiththatofaclassmate.
Discusstheitemsyouputquestionmarksbeside.
Compileaclasslistfordiscussion.
WhattypesofstructurescomeupthemostoftenClassifyingStructuresFigure4.
9Packingthematerialtogetherisimportantwhenconstructingsolidstructures.
SuggestedActivityB7QuickLabonpage105FrameStructuresFramestructuresaremadeofpartsfastenedtogether.
Thepartsareoftencalledstructuralcomponents.
Forexample,yourskeletonisaframestructure.
Itsstructuralcomponents—yourbones,ligaments,andtendons—arejoinedtogether.
Abicycleframeisanotherexampleofaframestructure(seeFigure4.
10).
sci7_ch04_3rd.
qxd7/15/085:15PMPage102Framestructurescanexistasjusttheframeorasaframecoveredbyacoating.
Forexample,atennisracket,dish-dryingrack,andspider'swebarestructuresthatareonlyframes.
Umbrellas,cars,andbats'wingsconsistofaframecoveredbysomesortofmaterial.
103Designersconsidertheformandthefunctionofastructureandtheforcesthatactonit.
Figure4.
11Theigloo,theeggcarton,andtheeggshellsthemselvesareshellstructures.
SomeveryfamousstructuresfromaroundtheworldincludetheEiffelTower,theGreatWallofChina,andMountEverest.
Canyouthinkofafamoussolidstructure,shellstructure,andframestructureBeginyoursearchatScienceSource.
TakeItFurtherShellStructuresMoststrong,hollowstructuresareshellstructures.
HaveyoueverbeeninsideaniglooorlookedupintoadomedroofHaveyoupouredmilkoutofacartonintoaglassorblownupaballoonIfso,youhaveseenashellstructure(Figure4.
11).
Sinceshellstructureshavespaceinsidethem,theyoftenmakegoodcontainers.
Theyalsouseverylittlematerialintheirconstruction.
Thismeansthattheyarequitelightfortheirsize.
Clothingcanevenbeconsideredshellstructures.
Figure4.
10Adelicatespider'swebandasturdycarframearebothframestructuresbecausetheyarebuiltlikeaskeleton.
sci7_ch04_3rd.
qxd7/15/085:15PMPage103CombinationStructuresManystructuresarecombinationstructuresbecausetheyarecombinationsofshell,frame,andsolidstructures.
Forexample,Figure4.
12showshowahouseisbuiltfromsolidstructures—bricks,nails,andpiecesofwoodcalledboards.
Theboardsarenailedtogetherintoaframethatgivesthebuildingstrength.
Strengthistheabilityofanobjecttowithstandforces.
Boththewallsandtheroofarenowframestructures.
Whentheframeisfinished,thewallandroofframesarecoveredwithplywood.
Windowsanddoorsareplacedintoholescutintheplywood.
Thebuildernowcoverstheoutsidewallwithbricksorsiding,andtheroofwithshingles.
Thesekeepthehousedrywhenitrains.
104UNITBStructures:FormandFunctionFigure4.
12Ahouseisbuiltfromsolidstructuresthatareputtogethertoformaframe.
Thewallsandtheroofformacoveringaroundtheframe.
sci7_ch04_3rd.
qxd7/15/085:15PMPage104B7QuickLab105Designersconsidertheformandthefunctionofastructureandtheforcesthatactonit.
Structuresthathavethesamefunctionmayhaveverydifferentforms.
Forexample,everychairisdesignedtosupporttheweightofapersonsittingonit(Figures4.
13,4.
14,and4.
15).
Inthislab,youwillbuilddifferentformsofchairsandtesttheirstrength.
PurposeTobuildstructurestoillustratesolid,frame,andshellstructuresProcedure1.
Sketchthreechairs:onethatcanbeclassifiedasasolidstructure,oneasaframestructure,andoneasashellstructure.
2.
Buildamodelofeachchairwithtoothpicksandmodellingclay.
Trytobuildthechairsapproximatelythesamesize.
3.
Thinkofadifferentstructureandrepeatsteps1and2forthestructureofyourchoice.
4.
Asaclass,designawaytotesttheabilityofeachchairtosupportweight.
Questions5.
Whatdidyounoticeabouttheuseofmaterialswhenyoubuiltsolidstructures,framestructures,andshellstructures6.
Whichtypeofstructurewasbestabletosupportweight7.
Whatgeneralizationscanyoumakeaboutsolid,frame,andshellstructuresBuildingSolid,Frame,andShellStructuresFigure4.
13Figure4.
14Figure4.
15Materials&Equipmenttoothpicksmodellingclaysci7_ch04_3rd.
qxd7/15/085:15PMPage105106UNITBStructures:FormandFunctionB8QuickLabUnpackingthePackagingPackagingisastructurethatyouencountereveryday.
Itisusedtoprotectotherstructuresduringtransport.
Packagingalsodisplaystheproductinthestore.
Somethingassimpleasabarofsoap(asolidstructure)maycomeinacardboardbox(shellstructure)thatmightbewrappedinplastic(anothershellstructure).
Inthisactivity,youwillstudypackagingasstructures.
Whenchoosingyourpackaging,selectawidevarietyofproducts,suchasfood,schoolsupplies,andelectronics.
PurposeTostudythestructuresinvolvedinpackagingProcedure1.
Youwilllookatallofthepackagingthatcamewithseveraldifferentproducts.
Keepthesetsofpackagingseparate.
2.
Takeonesetofpackaging.
WhatdiditcontainExaminethepackagingmaterial.
Describethepackagingqualitatively,inachartliketheoneinTable4.
1.
Aqualitativedescriptionisadescriptionjustinwords(e.
g.
,describingthecolour,thetexture,theshape).
3.
Describetheamountofpackagingquantitativelybyweighingitorfindingitsvolume.
Aquantitativedescriptionisonethatusesmeasurementstodescribesomething(e.
g.
,length,weight).
Table4.
1UnpackingthePackagingRecordingChart4.
Repeattheprocessforthreemoredifferentitems.
Questions5.
Compareyourchartwiththoseofyourclassmates.
Doyouagreewiththewayyourclassmatesdescribedthevariouspackages6.
WhatstructurescamewiththemostpackagingWhatstructurescamewiththeleastWhatstructuresdoyoubuythathavenopackaging7.
Comparetheweightorvolumeofeachstructurewiththeweightorvolumeofthepackagingitcamein.
Doyounoticeanytrends8.
Doyouthinkthepackagingdiditsjob9.
DoyouthinkeachpieceofpackagingwasnecessaryMaterials&EquipmentallofthepackagingassociatedwithseveralrecentpurchasespencilandpaperkitchenorbathroomscaleQualitativeAmountofType(s)ofProductDescriptionMaterialMaterialsci7_ch04_3rd.
qxd7/15/085:15PMPage106107Designersconsidertheformandthefunctionofastructureandtheforcesthatactonit.
WhattoDo1.
Thinkaboutapackedlunchandthestructuresusedtoholdeachitem.
WhattypesofstructurearetheyConsiderThisWithaclassmateorasawholeclass,discussthefollowingquestions.
2.
Arestructuresusedtoholdfoodusuallyshellstructures,framestructures,orsolidstructuresWhydoyouthinkthatis3.
WhatmaterialsarethestructuresthatholdyourlunchmadefromCantheybereusedoraretheydisposable4.
Howmightthechoicesofstructuresweusetoholdfoodaffecttheenvironment5.
Whichismoreofachallengetotransport:solidfoodorliquidfoodWhyStructuresinYourLunchboxKeyConceptReview1.
Define"structure"inyourownwords.
Describethreewaysinwhichyoucanclassifystructures.
2.
Classifythefollowingstructuresasasolidstructure,aframestructure,orashellstructure.
(a)athree-ringbinder(d)abasketballnet(b)atent(e)aniceskate(c)abackpack(f)asandcastleConnectYourUnderstanding3.
Makeachartwithfourcolumns.
Inthefirstcolumn,listfivestructuresusedineitherasoccerorabasketballgame.
(a)InColumn2,classifyeachstructureassolid,frame,orshell.
(b)InColumn3,describetheformofeachstructure.
(c)InColumn4,statethefunctionofeachstructure.
4.
Sometimestransportingstructuresexposesthemtoforcesthattheywouldnotencounterduringnormaluse.
(a)Listdifferentwaysthatyouhaveseenstructuresprotectedforshipping.
(b)Describeonewaythatyoufeeliseffective.
(c)Describeonewaythatyoufeelisnot.
(d)Whatdoyoudowithpackagingmaterialsafteryouunpackastructure5.
DoyouthinkadesignershouldbeginworkwithforminmindorwithfunctioninmindGivereasonsforyourthinking.
PractiseYourSkills6.
Thinkofastructurethatcanbeclassifiedasbothaframestructureandashellstructure.
Drawasimplediagramtohelpyouexplainwhythestructurecanbeclassifiedinbothways.
Formorequestions,gotoScienceSource.
4.
1CHECKandREFLECTSTSEB9ThinkingaboutScienceandTechnologysci7_ch04_3rd.
qxd7/15/085:15PMPage107
腾讯云双十一活动已于今天正式开启了,多重优惠享不停,首购服务器低至0.4折,比如1C2G5M轻量应用服务器仅48元/年起,2C4G8M也仅70元/年起;个人及企业用户还可以一键领取3500-7000元满减券,用于支付新购、续费、升级等各项账单;企业用户还可以以首年1年的价格注册.COM域名。活动页面:https://cloud.tencent.com/act/double11我们分享的信息仍然以秒...
mansora怎么样?mansora是一家国人商家,主要提供沪韩IEPL、沪日IEPL、深港IEPL等专线VPS。现在新推出了英国CN2 KVM VPS,线路为AS4809 AS9929,可解锁 Netflix,并有永久8折优惠。英国CN2 VPS,$18.2/月/1GB内存/10GB SSD空间/1TB流量/100Mbps端口/KVM,有需要的可以关注一下。点击进入:mansora官方网站地址m...
对于Megalayer云服务器提供商在之前也有对于他们家的美国服务器和香港服务器进行过评测和介绍,但是对于大部分网友来说需要独立服务器和站群服务器并不是特别的普及,我们很多网友使用较多的还是云服务器或者VPS主机比较多。在前面也有在"Megalayer新增香港VPS主机 1GB内存 50GB SSD 2M带宽 月59元"文章中有介绍到Megalayer商家有新增香港CN2优化VPS主机。那时候看这...
360安全卫士7 0下载为你推荐
96155北京住房公积金电话96155经常没人接?google竞价排名谷歌是靠什么关键词排名的?谷歌竞价有什么特点?有什么优势?手游运营手册2019新个税主要内容有哪些?可以简单说明一下吗?无线路由器限速设置路由器里面限速参数如何设置?缓冲区溢出教程适合黑客初级学者使用的黑客工具有那些 、金山杀毒怎么样金山杀毒软件咋样?微信如何建群微信可以建立两个人的群吗?有一个是自己蘑菇街美丽说蘑菇街、美丽说这类网站前期是怎么推广的?xv播放器下载xv播放器怎么下载?idc前线怎么知道我电脑是3兆的宽带?
四川虚拟主机 网页空间租用 免费cn域名 net主机 photonvps vultr美国与日本 100m独享 万网空间购买 沈阳主机托管 免费网络 114dns 万网主机 cdn服务 免费主页空间 789电视剧网 godaddyssl accountsuspended winserver2008 架设代理服务器 机柜尺寸 更多