1、第,2,课时 探究凸透镜成像规律,沪科版,八年级物理上册,第1页,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成
2、才路,1,、透镜是利用光,_,规律制成,透镜有两类:一类是中间比边缘厚透镜叫做,_,,如,_,镜片;另一类是中间比边缘薄透镜叫,_,,如,_,镜片。,温故知新:,折射,凸透镜,远视眼镜,凹透镜,近视眼镜,第2页,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元
3、成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,2,、,_,在透镜中心处,经过两个球面球心直线叫做透镜,_,。,3,、凸透镜对光有,_,作用,凹透镜对光有,_,作用。,4,、平行光经过凸透镜,将会聚到主光轴上一点,这个点称为凸透镜,_,,,_,到光心距离叫做,_,,一个透镜有两个,_,。,光心,主光轴,会聚,发散,焦点,焦点,焦距,焦距,第3页,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元
4、成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,凸透镜在生产、生活中含有广泛利用。,倒立、放大实像,倒立、缩小实像,正立、放大虚像,下面,我们来探究一下凸透镜成像特点。,第4页,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成
5、才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,探究问题:,f,F,O,凸透镜,试验方案:,光屏,物体,像虚、实,大、小,正、倒跟物距有什么关系呢?,第5页,状元成才路,状元成才路,状元
6、成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,(,1,)试验器材:,烛焰、透镜、光屏三者中心处于同一水平高度。,(,2,)两个物理名词
7、及试验前调整:,凸透镜、蜡烛、光屏、火柴、光具座,第6页,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,物
8、距:物体到光心距离,用,u,表示。,像距:像到光心距离,用,v,表示。,焦距:焦点到光心距离,用,f,表示。,2,倍,焦距:距离为焦距两倍(从光心开始),用,2,f,表示,物距(,u,),像距(,v,),第7页,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元
9、成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,进行试验与搜集证据,1.,设法获取凸透镜焦距。,2.,认识光具座,将试验器材按蜡烛、凸透镜、光屏次序放置在光具座上。,3.,蜡烛火焰经凸透镜后成缩小实像,将,u,、,v,值统计下来。,4.,蜡烛火焰经凸透镜后成放大实像,将,u,、,v,值统计下来。,5.,蜡烛火焰经凸透镜后成等大实像,将,u,、,v,值统计下来。,6.,蜡烛火焰经凸透镜后成放大虚像,将,u,值统计下来。,7.,蜡烛火焰放在凸透镜焦点处,观察是否能成像。,8.,改变物距,重复几次
10、上面试验操作。,第8页,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,凸透镜成像规律,第9页,状元成才路,
11、状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,试验序号,凸透镜焦距,f,/cm,像放大或缩小,像,正、倒,像,虚、实,
12、物距,u/cm,像距,v/cm,1,2,3,4,5,6,探究试验统计表,第10页,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状
13、元成才路,状元成才路,放映状态下显示,第11页,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,分析与论证,
14、1.,当物体位于凸透镜,2,倍焦距之外,时,成,缩小、倒立实像,;,第12页,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成
15、才路,状元成才路,2.,当物体位于凸透镜,1,倍焦距与,2,倍焦距之间,时,成,放大、倒立实像,;,第13页,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路
16、状元成才路,状元成才路,状元成才路,状元成才路,3.,当物体位于凸透镜,2,倍焦距,时,成,等大、倒立实像,;,第14页,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才
17、路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,4.,当物体位于凸透镜,1,倍焦距以内,时,成,放大、正立虚像,;,第15页,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状
18、元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,5.,当物体位于凸透镜,1,倍焦距,时,不能成像。,第16页,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,
19、状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,试验序号,物距,u,/cm,像放大或缩小,像,正、倒,像,虚、实,像距,v,/cm,1,u,2,f,缩小,倒立,实像,f,v,2,f,2,u,=2,f,等大,倒立,实像,v,=2,f,3,f,u,2,f,放大,倒立,实像,v,2,f,4,u,=,f,不能成像,5,u,f,放大,正立,虚像,v,u,第17页,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元
20、成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,试验中问题,1.,将烛焰、凸透镜、光屏依次放置在光具座上,调整烛焰、凸透镜、光屏使它们中心在,同一高度,,为了使烛焰像成在光屏中央。,2.,在此试验中,不论怎样左右移动光屏,在光屏上都不能展现烛焰像,原因可能有哪些?,(,1,)烛焰在焦点以内,(,2,)烛焰在焦点上,
21、3,)烛焰、凸透镜、光屏中心不在同一高度,(,4,)蜡烛到凸透镜距离稍大于焦距,成像在很远地方,光具座上光屏无法移动到该位置,第18页,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元
22、成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,3.,当透镜被遮拦二分之一和大半部分时光屏上像会怎么样?,像形状没有改变,但像会变暗,4.,凸透镜呈实像规律是:,上下颠倒、左右相反,5.,若烛焰在光屏上位置偏高,要想使像成在光屏中央应调整蜡烛是烛焰向上移动,或将凸透镜向下移动(像移动方向跟物体移动方向相反,透镜移动方向跟像移动方向一致)。,第19页,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,
23、状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,怎样测凸透镜焦距?,利用凸透镜成像特点:当,u,=2,f,时,,v,=2,f,,像,与物体等大,能够测出凸透镜焦距(,f,=,u,/2,),第20页,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成
24、才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,1,.,(,1,)如图所表示,把点燃蜡烛放在,_,处,光屏上出现缩小像,把点燃蜡烛放在,_,处,光屏上出现放大像;放在,_,处时,光屏上不会成像。,A,D,B,C,F,2,f,F,光屏,
25、A,C,D,测 试 题,第21页,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,(,2,)在物距不停减小过
26、程中,像距不停,_,,像大小不停,_,;当物距小于,_,时,不论怎样移动光屏,都不能在光屏上得到烛焰像。,增大,变大,1,倍焦距,A,D,B,C,F,2,f,F,光屏,第22页,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状
27、元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,F,F,B,A,2.,按要求画出光路图,经过焦点光线,折射后跟主轴平行;,跟主轴平行光线,折射后经过焦点;,经过光心光线经过透镜后方向不变。,第23页,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成
28、才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,F,F,B,A,跟主轴平行光线,折射后经过焦点;,经过焦点光线,折射后跟主轴平行;,经过光心光线经过透镜后方向不变。,第24页,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路
29、状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,状元成才路,试验序号,物距,u,/cm,像放大或缩小,像,正、倒,像,虚、实,像距,v,/cm,1,u,2,f,缩小,倒立,实像,f,v,2,f,2,u,=2,f,等大,倒立,实像,v,=2,f,3,f,u,2,f,放大,倒立,实像,v,2,f,4,u,=,f,不能成像,5,u,f,放大,正立,虚像,v,u,小 结,第25页,声 明,本文件仅用于个人学习、研究或观赏,以及其它非商业性或非盈利性用途,但同时应恪守著作权法及其它相关法律要求,不得侵犯本司及相关权利人正当权利。,除此以外,将本文件任何内容用于其它用途时,应取得授权,如发觉未经授权用于商业或盈利用途将追加侵权者法律责任。,武汉天成贵龙文化传输有限企业,湖北山河律师事务所,第26页,第27页,






