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1、1、物理学的研究对象是什么？、物理学的研究对象是什么？ 2、科学探究的一般步骤是什么？、科学探究的一般步骤是什么？1答：答：物理研究物理研究 力、声、热、光、电等现象。力、声、热、光、电等现象。2答答 1提出问题提出问题 2作出猜想作出猜想 3设计实设计实 验验 4实验验证实验验证 5得出结论得出结论 6交流合作交流合作 7提出新猜想提出新猜想Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation on
2、ly.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.第一章第一章 机械运动机械运动Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile
3、 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.学习目标学习目标n掌握秒表、刻度尺的使用n能就地取材粗略测量时间和长度n对误差有初步认识Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011
4、 Aspose Pty Ltd.猎猎 豹豹 追追 捕捕 羚羚 羊羊Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.速速 滑滑Evaluation only.Created with Aspos
5、e.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd. Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose
6、 Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.一、长度和时间的测量一、长度和时间的测量Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides
7、for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.那么什么叫测量呢？那么什么叫测量呢？n所谓测量，是指用实验的方法，将被测量（未知量）与已知的标准量（叫单位）进行比较，以得到被测量大小的过程；是对被测量定量认识的过程。Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with As
8、pose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.传说有一个胖子和一个瘦子各用自传说有一个胖子和一个瘦子各用自己的腰围做标准，测量同一段布的己的腰围做标准，测量同一段布的长度，因结果不同而互相争吵，这长度，因结果不同而互相争吵，这说明什么？说明什么？测量需要有统一的标准，测量需要有统一的标准，国际计量组织制定了一套国际统国际计量组织制定了一套国际统一的标准，这个统一的标准就叫一的标准，这个统一的标准就叫国际单位制国际单位制Evaluation only.Created with
9、Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.人人 头头 发发 的的 直直 径径10-4米米Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0
10、.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.原原 子子 直直 径径1010-10-10米米Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation on
11、ly.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.病病 毒毒 直直 径径10-7米米Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profi
12、le 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.地地 球球 赤赤 道道 周周 长长107米米Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.哈雷彗星
13、彗尾的长度哈雷彗星彗尾的长度1012米米Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.可观测到的宇宙距离可观测到的宇宙距离1027米米Evaluation only.Created with
14、 Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.为什么要测量？为什么要测量？ABAB长还是长还是CDCD长？长？中心的圆哪个面积大中心的圆哪个面积大? ?Evaluation only.Created with Aspose.Slides for
15、.NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.视觉是不可靠的视觉是不可靠的Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose
16、 Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.视觉是不可靠的视觉是不可靠的Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .N
17、ET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.常见的测量长度的工具常见的测量长度的工具刻度尺刻度尺卷尺卷尺游标卡尺游标卡尺螺螺旋旋测测微微器器Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.
18、2.0.0.Copyright 2004-2011 Aspose Pty Ltd.n测量长度最基本的工具是刻度尺。n下图是一些常用的测量工具，你使用过吗？长度的测量工具长度的测量工具Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2
19、011 Aspose Pty Ltd.长度国际单位是米米，符号m.M（兆）（兆）K（千）（千）d（分）（分）c（厘）（厘）m（毫）（毫）（微）（微）n（纳）（纳）Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose
20、 Pty Ltd.（1）长度的国际单位是）长度的国际单位是米米，符号，符号m.（2）其它常见的长度单位及符号。）其它常见的长度单位及符号。长度的单位长度的单位换算关系：换算关系：km km m m dm c m m m m n m dm c m m m m n m103101010103103千米、千米、分米、分米、厘米、厘米、毫米、毫米、 微米、微米、纳米纳米k md mc mm mmn mEvaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Asp
21、ose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.单位换算的格式单位换算的格式500m=_m500m= 500106 m= 5108 m42cm=_nm42cm= 42107 nm= 4.2108 nm167nm= 167 10-12 km= 1.67 10-10 km167nm= KmEvaluation only.Created with Aspose.Slides for .NET 3.5
22、 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.在下面各题中填上合适的单位1、教室门的高度约20（ ）2、课桌的高度约750（ ）3、常用圆珠笔的长度约1.5（ ）4、物理课本中一张纸的厚度约70（ ）5、教室每层楼高约33（ ）6、课桌高度约70（ ）7、一位中学生的身高约16.5（ ）8、练习册的
23、长度约为0 .22（ ）例题：umdmdmmmdmcmdmmEvaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.m ，dm，cm，mm有多长呢？能举例吗？有多长呢？能举例吗？mdmcmmm1角硬币
24、的厚度角硬币的厚度Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.长度的测量长度的测量n用前三看：n一看单位和 零刻线是否磨损n二看量程n三看最小分 度值，决定刻度尺的精确度和测量结果的有效值
25、n用时五会n一会选：根据测量要求选刻度尺n二会放：刻度尺要沿着所测量的直线n三会看：视线要与尺面垂直n四会读：估读n五会记：准确值、估计值、单位A放平：刻度尺要与物体被测边缘放平：刻度尺要与物体被测边缘平行。平行。B紧贴：刻度尺有刻度一面要紧贴紧贴：刻度尺有刻度一面要紧贴被测物。被测物。C对齐：零刻度线或整刻度线与被对齐：零刻度线或整刻度线与被测物体的边缘对齐。测物体的边缘对齐。Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty
26、 Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.例：图中用刻度尺测物体的长度，那一个正例：图中用刻度尺测物体的长度，那一个正确？（确？（ ） D没对齐、没对齐、没紧贴没紧贴没放平、没放平、没紧贴没紧贴没紧贴没紧贴正确正确Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2
27、011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.例例1：如下图，能正确测量出硬：如下图，能正确测量出硬币直径的是：币直径的是： DEvaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation o
28、nly.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd. 用最小刻度是毫米的刻度尺，测量一木用最小刻度是毫米的刻度尺，测量一木块的长度，如图块的长度，如图1所示，则此木块长度是（所示，则此木块长度是（ ）A、1.8厘米厘米 B、1.85厘米厘米C、7.85厘米厘米D、7.8厘米厘米B练 习Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Co
29、pyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.n思考：要测量一个硬币的直径，有哪些方法？n让硬币在地面沿直线滚动N周，测出直线的长度L，周长C=L/N。n用细线在硬币上绕三圈，量出细线的长度L，周长C=L/3。n把硬币放在纸上，贴着边缘用笔画一圈，再剪下对折即可直接在刻度尺上读出直径，算出周长。n如图，平移法。Evaluation only.Crea
30、ted with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.木块木块A的长度是的长度是_厘米厘米2.35练 习Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Prof
31、ile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.2.4木块木块A的长度是的长度是_ 厘米厘米练 习Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.
32、Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.n二、误差：测量值与真实值之间的差异。（物体的真实长度叫真实值。）n注意：误差和错误的区别：n误差不可避免，它是因为测量工具本身的精密程度、测量方法的完善程度等客观因素和测量者主观因素引起的。n错误是可以避免的，它主要是由于实验方法不正确、仪器使用不正确、读数不正确等原因引起的。 Evaluation only.Created with Aspose.Slides fo
33、r .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.误差误差: :例例:某同学三次测量某物体的长度分别是某同学三次测量某物体的长度分别是45.4cm;45.1cm; 45.3cm ,则该物体的长度是则该物体的长度是_ _.在测量时要进行在测量时要进行估读估读,估读有时偏大估读有时偏大,
34、有有时偏小时偏小,这样就会产生误差这样就会产生误差. 误差不是错误误差不是错误,不可避免不可避免. 多次测量取其平均值多次测量取其平均值,可减小这种误差可减小这种误差45.3cmEvaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-201
35、1 Aspose Pty Ltd.注意：误差与错误的区别注意：误差与错误的区别n所谓误差，是在正确测量的前提下，所测得的数值和真实值之间的差异，由于人的眼睛不能估得非常准，所以存在误差是不可避免的；而错误是由于不遵守测量仪器的使用规则，或读取、记录测量结果时粗心等原因造成的。所以，误差和错误是两个完全不同的概念。因此，学习时应特别注意两者的区别。n误差=测量值真实值（不会大于最小刻度值）Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose
36、 Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.误差产生的原因：误差产生的原因：n一、仪器误差：任何仪器都有一定的精度，仪器本身会有一些误差。n二、人为误差：由于人的感官的鉴别能力的局限性，在瞄准读数方面都会产生误差。n三、外界条件影响：如温度、湿度、风力、日照、气压、大气折光等因素，必然会造成误差。Evaluation only.Created with Aspose.Slides for .NE
37、T 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.注意不能认为测量工具的最小刻度注意不能认为测量工具的最小刻度越小越好越小越好 要根据实际情况选择恰当的测量工具要根据实际情况选择恰当的测量工具 测量需要达到的准确程度跟测量的测量需要达到的准确程度跟测量的要求有关，测量能够达到的准确程要求有关，
38、测量能够达到的准确程度由刻度尺的最小刻度所决定。度由刻度尺的最小刻度所决定。Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.误差误差n误差不可避免。n减少误差的方法：可以通过改进测量方法、选用
39、更精确的测量工具、多次测量取平均值等办法来减小误差。Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd. 有一位同学用毫米刻度尺先后有一位同学用毫米刻度尺先后四次测量一个物体的长度。测量结四次测量
40、一个物体的长度。测量结果是果是1.41厘米，厘米，1.52厘米，厘米，1.42厘厘米，米，1.44厘米，根据记录分析，刻厘米，根据记录分析，刻度尺的分度值度尺的分度值 测量结果有测量结果有错误的是错误的是_厘米，物体的厘米，物体的长度是长度是_厘米。厘米。1.421.52练 习mmEvaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides fo
41、r .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.小资料小资料小资料小资料有趣的人体尺度有趣的人体尺度 古古代代中中国国、古古埃埃及及、古古罗罗马马，不不管管是是东东方方文文化化还还是是西西方方文化，最早的尺都来源于人体，这是为什么文化，最早的尺都来源于人体，这是为什么? 你你也也许许会会说说用用身身上上的的尺尺子子方方便便呗呗！这这当当然然是是主主要要的的。但但是是，还还有有一一个个更更深深一一层层的的原原因因，那那就就是是人人体体各各部部分分的的尺尺寸寸有着规律，不信，咱们试试看。有着规律，不信，咱们试
42、试看。 你你用用皮皮尺尺量量一一量量拳拳头头的的周周长长，再再量量下下你你的的脚脚底底长长，你你会会发发现现，这这两两个个长长度度很很接接近近。所所以以，买买袜袜子子时时，只只要要把把袜袜底在自己的拳头上绕一下，就知道是否合适。底在自己的拳头上绕一下，就知道是否合适。Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET
43、3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.小资料小资料小资料小资料有趣的人体尺度有趣的人体尺度 你你为为你你的的父父母母或或兄兄长长量量一一量量脚脚长长和和身身高高，你你就就会会发发现现其其中中的的奥奥秘秘：身身高高往往往往是是脚脚长长的的7倍倍。高高个个子子要要穿穿大大号号鞋鞋，矮矮个个人人要要穿穿小小号号鞋鞋就就是是这这个道理。个道理。Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright
44、 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.小资料小资料小资料小资料有趣的人体尺度有趣的人体尺度 侦侦察察员员常常用用这这个个原原理理来来破破案案：海海滩滩上上留留下下了了罪罪犯犯的的光光脚脚印印，量量一一下下脚脚印印长长是是25.7厘厘米米，那那么么，罪罪犯犯的的身身高高大约是多少呢大约是多少呢?(25.7cm7179.9cnl) 小小琴琴为为妈妈妈妈买买鞋鞋
45、，她她忘忘了了妈妈妈妈的的鞋鞋号号，只只记记得得妈妈妈妈身身高高是是168厘厘米米，你你能能帮帮她她算算一一算算买买几几号号鞋鞋吗吗?全全国国统统一一鞋鞋号号是是根根据据脚脚长长编编定定的的，如如24号号，就就适适合合脚脚长长为为24厘厘米米的人穿，算出脚长就可以算出鞋号了。的人穿，算出脚长就可以算出鞋号了。Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with As
46、pose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.时间的测量时间的测量n时间的单位：n时（h）；分（min）；秒（s）n计时工具：停表Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Clien
47、t Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.时钟的发展Evaluation onl
48、y.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.三、时间的单位及测量1、在国际单位制中，时间的单位是秒（s）。 常用的单位还有分（min）和小时（h）。2、时间单位的换算关系：1 min=60 s 1h=60min=36
49、00 sEvaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.三时间的单位及测量：三时间的单位及测量：国际单位制中的单位：秒（国际单位制中的单位：秒（s）常用单位：分钟（常用单位：分钟（min）、小
50、时）、小时(h)、天、年、天、年换算关系：换算关系： 1年年365天，天，1d24h，1h60min，1min60s。Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.学会使用停表n请你仔细观察
51、图示秒表：（1）大表盘一周量度的时间是（ ），分度值是（ ）。（2）小表盘一周量度的时间是（ ），分度值是（ ）。60s0.2s30min1minEvaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd
52、.n学习停表的使用方法；测试两次连续按表的时间。n讨论：这个时间对于计时测量带来的实验误差。Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.1、测量一次脉搏跳动的时间。 方法：测量脉搏一分钟内
53、跳动次数n，则：t=n/60 讨论：为什么不直接测量一次脉搏跳动的时间？ 可以减少实验误差。2、测定单摆来回摆动一次所需时间周期。 方法：测定单摆完成摆动50个周期所需要的时间t，则来回摆动一次所需要的时间t0： t0 =t/50Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile
54、5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.n1、在国际单位制中，长度的基本单位是_，符号是_测量长度的基本工具是_，使用前首先要观察它的_、_和_ ；n2、完成下列单位换算 （要求写出中间过程）n（1）0.05m=_cmn（2）5mm=_mn（3）0.007m=_nm课堂巩固70.0055零刻度线零刻度线分度值分度值量程量程刻度尺刻度尺m米米Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose
55、Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.1 1、用分度值是、用分度值是1mm 1mm 的刻度尺，直接测物体的长的刻度尺，直接测物体的长度，在下列所记录的数据中，正确的是（度，在下列所记录的数据中，正确的是（ ） A A、0.820m B0.820m B、82.0cm 82.0cm C C、82.00 D82.00 D、820.0mm820.0mm2 2、如图、如图1 1是用厚刻尺测量木块的长度
56、，其中正是用厚刻尺测量木块的长度，其中正确的测量图是（确的测量图是（ ）ADBCDBEvaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.3 3、根据下图可读出：物休根据下图可读出：物休ABAB的长
57、度为的长度为_,_,物物体体A A的长度是的长度是 。4 4如右图所示。用刻度尺测一木块的长度，这如右图所示。用刻度尺测一木块的长度，这支刻度尺的最小刻度值是支刻度尺的最小刻度值是 ，木块的长度为，木块的长度为 厘米，测量的准确值为厘米，测量的准确值为 ，估读的数字为，估读的数字为 。Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides
58、for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.思考讨论n1、使用刻度尺时，是否一定要从刻度为0的位置量起？n2、用力拉皮尺来测量长度，这样测量结果准确吗？n3、厚木尺在测量时的放法与书本图示不同，为什么？Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.
59、Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd. 会选：会选： 在实际的测在实际的测量中量中, ,并不是分并不是分度值越小越好度值越小越好, ,测量时应先根测量时应先根据实际情况确据实际情况确定需要达到的定需要达到的程度程度, ,再选择满再选择满足测量要求的足测量要求的刻度尺刻度尺. .Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Asp
60、ose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.认清刻度尺的单位、零刻度线的位认清刻度尺的单位、零刻度线的位置、量程、分度值置、量程、分度值. .会认：会认：正确使用刻度尺正确使用刻度尺零刻度线量程分度值量程:_单位单位: _分度值:_(0-8cm)0.1cmcm单位单位Evaluation only.Created with Aspose.Slides for .NET 3.5 Client
61、 Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.会放：会放：零刻度线或某一数值刻度线零刻度线或某一数值刻度线对齐对齐待测物待测物的一端，使刻度尺有刻度的边的一端，使刻度尺有刻度的边紧靠紧靠待测待测物体，物体，放正放正尺的位置，不能倾斜。尺的位置，不能倾斜。 Evaluation only.Created with
62、Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.会看：会看：视线与刻度尺尺面视线与刻度尺尺面垂直垂直。 Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.
63、2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd. 会读：会读：. .读数时，要估读到读数时，要估读到分度值的下一位分度值的下一位. .记录测量结果时，要写出记录测量结果时，要写出数字和单位数字和单位。分度值：分度值：0.1cmcmEvaluation only.Created with Aspose.Slides for .NET 3.
64、5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.练习练习: (会认会认,会放会放,会看会看,会读会读,会选会选)1,用刻度尺测量书本的长度和宽度用刻度尺测量书本的长度和宽度.2,测量教室的长度测量教室的长度. 3,活动活动:如何用刻度尺测量纸张的厚度如何用刻度尺测量纸张的厚度?累积法累积法:测出测出
65、n张纸的总厚度张纸的总厚度,再除以纸的张数再除以纸的张数.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.练习练习:量程量程:_分度值分度值:_木块长度木块长度:_量程量程:_分度值分度值:_
66、木块长度木块长度:_分度值分度值越小越小,读数读数越精确越精确.0-8cm1cm0.1cm4.3cm4.36cm0-8cm哪个数值更精确哪个数值更精确?说明说明:Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose
67、 Pty Ltd.量程量程:_分度值分度值:_木块长度木块长度:_0-8cm0.1cm4.36cm4.36cm准确值准确值4.3cm 估计值估计值0.06cm分度值为分度值为0.1cm因为读数时，估读到分度值下一位，所以因为读数时，估读到分度值下一位，所以分度值要分度值要看测量结果的倒数第二位看测量结果的倒数第二位。Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created wit
68、h Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.练习练习:用刻度尺测某物体的长度是用刻度尺测某物体的长度是1.34cm,准确值是准确值是_cm, 估计值是估计值是_,此刻度尺是此刻度尺是_,它的分度值它的分度值 是是_cm.AB得出得出:0.11.30.04cmB数值的数值的倒数第二位的单位长度倒数第二位的单位长度是刻度尺的分度值是刻度尺的分度值.读数包括读数包括:准确值准确值 估计值估计值和和单位单位Evaluation only.Created with Aspos
69、e.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.读出下列物体的长度：读出下列物体的长度： 0 cm 1 2 3 4 5 6 7 0 cm 1 2 3 4 5 6 7读出下列物体的长度：读出下列物体的长度： 0 cm 1 2 3 4 5 6 7 0 cm 1 2
70、 3 4 5 6 76.30cm6.00cm= m0.0600Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.练习练习:没没”0”刻度的刻度尺能测量物体的长度吗刻度的刻度尺能测量物体的长度吗?
71、分度值是分度值是:_木块长度是木块长度是:_2.1cm1cmEvaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.例如例如: :现有现有卷尺卷尺( (分度值分度值1cm)1cm)和和游标卡尺游标卡尺
72、( (分度值分度值0.1mm)0.1mm)根据需要选择测量下述根据需要选择测量下述物体所用的工具物体所用的工具: :1 1、测量跳远长度需用、测量跳远长度需用_._.2 2、测量铜丝的直径需用、测量铜丝的直径需用_._. Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.
73、0.0.Copyright 2004-2011 Aspose Pty Ltd. 测量长度的特殊方法测量长度的特殊方法（1 1）辅助工具法辅助工具法 适于测圆、圆柱体的直径和圆锥体的高适于测圆、圆柱体的直径和圆锥体的高Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0
74、.Copyright 2004-2011 Aspose Pty Ltd.1 1、测较短的曲线，例如地图册上、测较短的曲线，例如地图册上 的铁路线长的铁路线长2 2、测较长的曲线例如运动场的跑道、测较长的曲线例如运动场的跑道（2 2）化曲为直）化曲为直Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Clien
75、t Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.测纸的厚，细丝直径测纸的厚，细丝直径（3 3）累计法）累计法( (积多求少）积多求少）Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.再见再见南田坪中学南田坪中学赵宗仁赵宗仁Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Copyright 2004-2011 Aspose Pty Ltd.
