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笔者近日在一本《初中物理竞赛讲座》中看到如下的一道题: 一块长0.8米的平面镜竖直挂在墙上固定不动,一个高1.6米的甲同学站在平面镜前恰好能看到自己全身的像。现有一个1.5米的乙同学和1.7米的丙同学站在甲同学的位置上,下列判断可供选择: ①站在原处就能看见自己全身的像。 ②走近平面镜才能看见自己全身的像。 ③远离平面镜才能看见自己全身的像。 ④无论怎样也看不见自己全身的像。
The author recently saw the following question in a “Seminar for junior high school physics competitions”: A 0.8-meter-long flat mirror is hung vertically on a wall, and a 1.6-meter-high student stands in front of the plane mirror. The image of my own body. There is a 1.5-meter B classmate and a 1.7-meter class C class student standing in class A. The following judgments are available: 1 Standing in the same place, you can see the image of yourself. 2 approach the plane mirror to see the image of his body. 3 You can see the image of your whole body away from the plane mirror. 4 I can’t see my whole body in any way.