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SCIENCE STUDY

Updating the way we measure

作者:BY DANIEL DAUGHERTY
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基于量子物理:“千克”概念被重新定义。 词数391 建议阅读时间6分钟

In the modern world, almost everything you can think of depends on exact measurements. But how do we know if a ruler is exactly one meter in length? How do we know if a watermelon weighs a kilogram?
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