eli5: How are squirrels able to survive a fall at terminal velocity?
In: 6
Another example of the universal ‘square-cube law’!
The mass of the small critter – and therefore the size of the force from gravity pulling them down – comes from the animal’s volume, which changes by their width times their length times their height – that is, three measurements multiplied together, which is something cubed.
The wind resistance that slows them down, acting against the force of gravity, changes by their length by their width – only two measurements multiplied together, which is something squared.
As the critter gets smaller, that mass and the force from gravity decreases a lot faster than the force from wind resistance. So small critters fall a lot more slowly.
Then when they land – The strength of their bones changes by the cross-sectional area of those bones, and the strength of the muscles by their cross sectional area. Those areas are the width of the bones and muscles squared. But again, the impact forces go down with the animals mass, which comes from volume, which is a measurement cubed. So their legs and bodies, compared with their size, are a lot stronger, and so can absorb these impact forces a lot more.
This square-cube law crops up everywhere. You’ll be surprised how often it drives things.
eli5: How are squirrels able to survive a fall at terminal velocity?
In: 6
Another example of the universal ‘square-cube law’!
The mass of the small critter – and therefore the size of the force from gravity pulling them down – comes from the animal’s volume, which changes by their width times their length times their height – that is, three measurements multiplied together, which is something cubed.
The wind resistance that slows them down, acting against the force of gravity, changes by their length by their width – only two measurements multiplied together, which is something squared.
As the critter gets smaller, that mass and the force from gravity decreases a lot faster than the force from wind resistance. So small critters fall a lot more slowly.
Then when they land – The strength of their bones changes by the cross-sectional area of those bones, and the strength of the muscles by their cross sectional area. Those areas are the width of the bones and muscles squared. But again, the impact forces go down with the animals mass, which comes from volume, which is a measurement cubed. So their legs and bodies, compared with their size, are a lot stronger, and so can absorb these impact forces a lot more.
This square-cube law crops up everywhere. You’ll be surprised how often it drives things.
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