The world’s most accurate clocks

In 1967, researchers gathered to answer one question: how long is a second? It might seem obvious. A second is the tick of a clock or the swing of a pendulum. But how precise are those measurements? And what is that length based on?

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  1. Do you think life would be better or worse if we stopped using clocks altogether? Think about your answer and discuss it with members of your household.
  2. Write a script for a film about a day when time starts moving backwards.