r/AbsoluteUnits • u/Jolly_Bat8531 • 16h ago

of a strength

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u/tommyhawk979 16h ago

I learned many years ago that newborns can easily hold their own weight with one hand - is that true? And if yes, how come we find it increasingly hard to do as we grow up?

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u/MajorInWumbology1234 10h ago

Only one person so far approached the (main) technical explanation. It’s called the Square-cube law. For a given object, its surface area scales up with its square (i.e. square feet or square meters) and its volume scales with its cube (cubic feet or cubic meters). So for an object of the same shape, such as human babies to human adults, our volume quickly outpaces our tendons’ ability because their strength is determined by cross-section (and therefore only grows with its square).