Who decides how long a second is? - John Kitching
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YouTubeTED-Ed
Who decides how long a second is? - John Kitching
Discover how scientists developed atomic clocks, which use the vibrations of atoms to measure and maintain a globally consistent time. -- In 1967, researchers gathered to answer a long-running scientific question: just how long is a second? It might seem obvious at first. A second is the tick of a clock, the swing of a pendulum, the time it ...
2.7M viewsJan 19, 2021
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