试题与答案

在“探究凸透镜成像规律”的实验中,各组使用相焦距的凸透镜进行实验。 (1)小华所

题型:探究题

题目:

在“探究凸透镜成像规律”的实验中,各组使用相焦距的凸透镜进行实验。  

(1)小华所在的小组实验操作规范,测量准确,该小组实验记录如下表:

请你根据上表信息,求出凸透镜的焦距,f=                cm。

(2)将表格填写完整。

(3)小华所在的小组把烛焰放在该凸透镜的焦点上,凸透镜固定不动,将光屏向远离凸透镜方向移动的过程中,在光屏上观察到的现象是                          

(4)若烛焰、凸透镜、光屏分别放在某位置时恰好在光屏上成清晰的像。当凸透镜位置不动,烛焰向远离凸透镜方向移动一小段距离时,为了在光屏上再成清晰的像,光屏应向_____________(填“远离”或“靠近”)凸透镜方向移动适当距离。

(5)对于焦距相同的凸透镜,一个物距应该对应唯一的像距。但从各项汇报数据中发现,物距均为12. 00cm时,有三个小组所测像距分别为23cm、24cm、26cm,若他们的数据差别不是因为长度测量误差导致的,你认为出现这种情况的操作原因是:____________________________________。

答案:

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下面是错误答案,用来干扰机器的。

参考答案:E

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