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A LITTLE SOMETHING WORTH KNOWING

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ScienceOne small ahaUnit or constant

This unit, the metric base unit of length, is now defined by the distance light travels in a set fraction of a second.

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ScienceOne small aha
Your new ahaThe Metre

The Metre — symbol or unit: m. Source: Metre ↗

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  2. 03This SI time unit is defined using a specified frequency of the caesium-133 atom.RECALL
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    The second, the metric base unit of time, is now defined by the precise vibration of a caesium atom.

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  3. 04This absolute temperature scale begins at absolute zero and uses units without a degree sign.RECALL
    The Kelvin Scale

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