试题与答案

当光线垂直入射到()棱镜的斜面上,经两次直角面的反射,改变其光轴的方向为90度。A.

题型:单项选择题

题目:

当光线垂直入射到()棱镜的斜面上,经两次直角面的反射,改变其光轴的方向为90度。

A.直角 

B.平面 

C.锐角 

D.钝角

答案:

参考答案:A

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