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Light beam,mirror question
If i put a lazer pointer in a vaccum cube and the inner surface of the box is all
mirror.
I turn it on and off it in one second.
Shouldnt the beam be reflecting for unlimited times and the inside of the cube is
bright forever?
*the cube is vaccum
I know it is false but how come... The beam should not lose energy when bouncing off the mirrors in theory?
Thank you very much :/
2 個解答
- 天同Lv 77 年前最愛解答
There is no perfect mirror. On reflection on a surface, part of the incident light energy is reflected, but part of it is absorbed. Hence, the brightness inside the cube would gradually dies down, though this may take a long time on well polished mirror surfaces.
- 匿名7 年前
這家不錯*****買幾次啦真的一樣
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