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１秒の長さはどうやって決める？ ― ジョン・キッチング
2,316,828 views |
ジョン・キッチング |
TED-Ed
• January 2021
Read transcript
1967年、積年の科学的問題に答えを出そうと、研究者たちが集結しました。「１秒」は どのくらいの長さなのか？一見、答えは簡単そうです。１秒は、秒針がカチッとなる間隔とか、振り子の往復、「１」と数える長さなど。しかし、このような計測はどの程度、正確でしょう？１秒の長さの基準となるものは 何？この時間の基本単位を科学的にどう定義しているのかを、ジョン・キッチングが詳しく解説します。 監督：チョフ・クーン ナレーション：アディソン・アンダーソン
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