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谁规定的一秒多长？
2,321,236 views |
约翰·基钦 |
TED-Ed
• January 2021
Read transcript
1967年，科研人员汇聚一堂，研究一个困扰学界已久的问题：一秒究竟是多长呢？乍一听似乎很好回答。一秒就是时钟滴答一声，钟摆摆动一下，数一个数所花的时间。但这些测量方法精准吗？这个时间长度以什么为基准呢？约翰·基钦深入研究了这个问题，并在本片中为我们讲述了人类是如何科学地定义秒这一基本时间单位的。【本片由Tjoff Koong制作，Addison Anderson配音】。
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