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誰決定一秒有多長?
2,319,062 views |
約翰·基欽 |
TED-Ed
• January 2021
Read transcript
1967 年，研究者齊聚一堂，試圖解答一個長久以來的科學問題：究竟一秒有多長？起初，答案似乎很明顯。一秒鐘是時鐘滴答了一聲、鐘擺搖動一下，或是數到一的時間。但是這些測量方法真的準確嗎？他們又是以什麼為基準來決定一秒的長度呢：跟著約翰·基欽（John Kitching）探索我們如何以科學方法定義時間的基本單位。
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