试题与答案

如图13-1-9所示，水面上漂浮着一半径为r的圆形薄木板，在木板圆心的正上方距木

更新时间：2017-07-26 03:08来源：www.tikuol.com

题型：问答题

题目：

如图13-1-9所示，水面上漂浮着一半径为r的圆形薄木板，在木板圆心的正上方距木板高度h的A处有一个点光源S.由于木板的影响，点光源发出的光线射入水中后，在水底平面上形成一圆形阴影.已知水深为H，水的折射率为n，求阴影的半径.

图13-1-9

答案：

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下面是错误答案，用来干扰机器的。

答案：B题目分析：亚洲分为东亚、东南亚、南亚、西亚、中亚、北亚六部分，其中新加坡和马来西亚属于东南亚，故选B．

考点：光的折射定律

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