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Fun fact from the author of Physics for poets

He points out that an egg made of gold will fall down in water noticeably faster than one made of aluminum (okay, I'm adjusting things here). Why? not because they have noticeably different rates of acceleration (they don't, as Galileo pointed out). Rather because they have different terminal velocities. Tim: is that true? If so, we can try to rid the Aristotelians of the embarrassment caused by Galileo by claiming that Aristotle, in saying that a denser things falls faster, had terminal velocity in mind. Not entirely a joke, as he had in mind the relation between the push exerted by an object and the resistance of its environment. So maybe if there had been a tower as high as the Burj Dubai, the results might have been different.

Oh, but the truth is that Aristotle was unaware of terminal velocity. He noted in three places (Twice in the Physics and once in On the Heavens) that things accelerated as they got closer to the earth, giving the impression that they would continue doing so indefinitely.

Comments

Unknown said…
It's true.
4:56 PM
Leo White said…
This comment has been removed by the author.
11:23 PM
Leo White said…
Lemmee try that again...
But isn't there a point at which the resistance posed by the air equals the downward force of gravity, so that accelration stops? For example, I think that at a certain point skydivers stop accelerating when their velocity has reached somewhere around 160 to 200 mph.
11:25 PM
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