andperformancetestcopiesoftherecord.Ifnecessary,reviewshouldbecarriedout;4)forspringhangers(includedsimplespring,hangersandconstantsupporthangers)itshouldalsoberecognizedassettingandlockingofloads.5)checkthesurfacequality,foldedlayeringandwithoutcracks,rustandotherdefects.5)aftercompletionofthetestandcontroldrawingnumberonebyone,byseriesbaled.Coloralloysteelparts,thepartsmarkinginstallationlocationandrotationaboutthedirectionyouwant.7.3.14.hangersinstallation7.3.14.1hangerlayouta.acleardesignofhangershouldbeinstalledstrictlyinaccordancewiththedrawingsanddesignsshallnotbeinstalledwrong,missing,etc.B.ownarrangementofpipingsupportandhangersetandselectionshouldbebasedoncomprehensiveanalysisofgenerallayoutofpipingsystems;coldinstallationofsteampipewithparticularattentionreservedforcompensationofthermalexpansiondisplacementandorientation.C.supportsystemsshouldberationaltowithstandpipeloads,staticloadandincidentalload;reasonablepipingdisplacement;guaranteedundervariousconditions,stressarewithintheallowedrange.Strength,stiffness,andmeetrequirementstopreventvibrationandsoothingwater,withoutaffectingtheadjacentequipmentmaintenanceandotherpipinginstallationandexpansion.D.equipmentconnectedtotheinterfacetomeetpipelinethrust(torque)limitrequirements;increasethestabilityofpipingsystemstopreventpipeline...Tubewallthickness(mm)2-34-67-10weldformnoslopemouthweldstrengtheningheighth(mm)1-1.51.5-2weldwidthb(mm)5-67-6hasslopemouthweldstrengtheningheighth(mm)1.5-22weldwidthb(mm)coverhadeachedgeslopemouthabout2mmargonarcweldingweldstrengtheningsurfaceheightandwidthtubewallthickness(mm)2--33--45--6weldformweldstrengtheningheighth(mm)1-1.51.5-22-2.5widthb(mm)初中物理凸透镜成像规律及其应用专题复习【中考要求】1、通过实验,认识凸透镜的会聚作用和凹透镜的发散作用。2、探究并知道凸透镜成像的规律。3、了解凸透镜成像的应用凸透镜成像是中考热点,在中考中常以填空、选择、作图或实验的形式出现。【考点集训】考点①透镜1、透镜的概念:透镜有两类:中间厚,边缘薄的叫_________。中间薄,边缘厚的叫_________。凸透镜对光线有_________作用,所以又叫_________透镜。凹透镜对光线有_________作用,所以又叫_________透镜。主轴:通过两个球面球心的线叫做透镜的_________。光心:光线通过透镜上某一点时,光线传播方向不变______,这一点叫光心。焦点:平行于主光轴的光线经凸透镜折射后会聚在主光轴上一点(经凹透镜折射后要发散,折射光线的反向延长线相交在主轴上一点)这一点叫透镜的______,焦点到光心的距离,叫______,用___表示。2、凸透镜的光学性质:a平行于主光轴的光线经凸透镜折射后过焦点;b过焦点的光线经凸透镜折射后平行于主光轴;c过光心的光线方向不变。考点②凸透镜成像规律及应用:物距u像的性质像距v应用倒、正放、缩虚、实u2fu=2ffu2fuf口诀:一倍焦距分虚实,二倍焦距分大小。物在一倍焦距外,异侧光屏实像倒。物近像远像变大,物远像近像变小。考点③透镜应用眼睛和眼镜1、成像原理:从物体发出的光线经过_________等一个综合的凸透镜在视网膜上行成______,______的___像,分布在视网膜上的视神经细胞受到光的刺激,把这个信号传输给大脑,人就可以看到这个物体了。2、近视及远视的矫正:近视眼要戴___透镜,远视眼要戴___透镜.五、显微镜和望远镜1、显微镜:显微镜镜筒的两端各有一组透镜,每组透镜的作用都相当于一个凸透镜,靠近眼睛的凸透镜叫做目镜,靠近被观察物体的凸透镜叫做物镜。来自被观察物体的光经过物镜后成一个放大的实像,道理就像投影仪的镜头成像一样;目镜的作用则像一个普通的放大镜,把这个像再放大一次。经过这两andperformancetestcopiesoftherecord.Ifnecessary,reviewshouldbecarriedout;4)forspringhangers(includedsimplespring,hangersandconstantsupporthangers)itshouldalsoberecognizedassettingandlockingofloads.5)checkthesurfacequality,foldedlayeringandwithoutcracks,rustandotherdefects.5)aftercompletionofthetestandcontroldrawingnumberonebyone,byseriesbaled.Coloralloysteelparts,thepartsmarkinginstallationlocationandrotationaboutthedirectionyouwant.7.3.14.hangersinstallation7.3.14.1hangerlayouta.acleardesignofhangershouldbeinstalledstrictlyinaccordancewiththedrawingsanddesignsshallnotbeinstalledwrong,missing,etc.B.ownarrangementofpipingsupportandhangersetandselectionshouldbebasedoncomprehensiveanalysisofgenerallayoutofpipingsystems;coldinstallationofsteampipewithparticularattentionreservedforcompensationofthermalexpansiondisplacementandorientation.C.supportsystemsshouldberationaltowithstandpipeloads,staticloadandincidentalload;reasonablepipingdisplacement;guaranteedundervariousconditions,stressarewithintheallowedrange.Strength,stiffness,andmeetrequirementstopreventvibrationandsoothingwater,withoutaffectingtheadjacentequipmentmaintenanceandotherpipinginstallationandexpansion.D.equipmentconnectedtotheinterfacetomeetpipelinethrust(torque)limitrequirements;increasethestabilityofpipingsystemstopreventpipeline...Tubewallthickness(mm)2-34-67-10weldformnoslopemouthweldstrengtheningheighth(mm)1-1.51.5-2weldwidthb(mm)5-67-6hasslopemouthweldstrengtheningheighth(mm)1.5-22weldwidthb(mm)coverhadeachedgeslopemouthabout2mmargonarcweldingweldstrengtheningsurfaceheightandwidthtubewallthickness(mm)2--33--45--6weldformweldstrengtheningheighth(mm)1-1.51.5-22-2.5widthb(mm)次放大作用,我们就可以看到肉眼看不见的小物体了。2、望远镜:有一种望远镜也是由两组凸透镜组成的。靠近眼睛的凸透镜叫做目镜,靠近被观察物体的凸透镜叫做物镜。我们能不能看清一个物体,它对我们的眼睛所成“视角”的大小十分重要。望远镜的物镜所成的像虽然比原来的物体小,但它离我们的眼睛很近,再加上目镜的放大作用,视角就可以变得很大。【常见题型】类型一:解释现象1、某物体放在凸透镜前20cm处时,在光屏上得到了物体倒立缩小的清晰实像,则该凸透镜的焦距可能是()A.20cmB.15cmC.10cmD.5cm2、观察洋葱表皮细胞和观察蜗牛爬行用到的工具分别是()A.显微镜、放大镜B.放大镜、放大镜C.显微镜、显微镜D.放大镜、显微镜3、右图中a、b是同一人的两幅照片,b图中他拿的眼镜()A.属于凸透镜,可用于矫正近视眼B.属于凸透镜,可用于矫正远视眼C.属于凹透镜,可用于矫正远视眼D.属于凹透镜,可用于矫正近视眼4、放电影时,电影胶片上的图案经凸透镜在银幕上成的是()A、倒立、放大的虚像B、正立、放大的实像C、正立、放大的虚像D、倒立、放大的实像5、“五·四”青年节那天,学校请来摄影师给我们拍毕业照,列好队后,摄影师发现有几位同学没有进入取景框内,这时他重新调整照相机的正确方法是()A.照相机向前移,镜头向前伸B.照相机向前移,镜头向后缩C.照相机向后移,镜头向前伸D.照相机向后移,镜头向后缩6、检修工人在查看线路密集的电路板时,为了看清线路的连接情况,常透过一个较大的透镜进行观察,这个透镜应该是________透镜(填“凸”或“凹”),工人看到的是放大的________(填“实”或“虚”)像,电路板到透镜的距离应________焦距;检修时还用到了照明灯,这是为了照亮________(填“透镜”或“电路板”).类型二:凸透镜成像实验1、小明用凸透镜、蜡烛、光屏和刻度尺等器材探究凸透镜成像规律。⑴