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Q & A: Galileo and Einstein vs. Aristotle

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Most recent answer: 08/14/2016
Q:
http://timeblimp.com/?page_id=174
Aristotle was always right, heavy falls faster. Take ping-pong sized or building sized hollow light metal balls chromium or such, fill one with lead/radium, fill the other with feathers, the like. Regardless of drag, regardless of vacuum, just take a transport plane up to the edge of the atmosphere and drop them. There are many things not just laws that are wrong in mathematics that have never been corrected. The ones that speak up probably are ignored or worse for reasons unknown. No I'm not going to bring up or go over any more, just thought to put this out there, I'm not sure why because as I'm typing this there certainly has to be others out there that have run in to these mistakes that have never been corrected. If you find this and others to be true why not publish, FIX IT ? Today was Sunday, August/14/2016 Aaah error , I didn't have any specific website, all of them how about that? THERE IS NO SHORTAGE look for yourself, yes, I would say the majority are wrong, take a look. Okay I'll pick on just to get this to go through.
- MW (age oldenough)
A:

It's unfortunate that the site you listed, which does a nice job of describing some deep ideas, exaggerated the practical implications. The rate at which things fall through the atmosphere does indeed depend on weight, area, shape, etc. for objects much larger than ping-pong balls, unlike what they say. 

Nevertheless, your version, claiming that Aristotle was right that the rate of fall depends just on weight, is wrong in a much deeper sense. It's empirically wrong, since for the same weight different shapes give different rates of fall through the atmosphere, and for different weights the rates of fall are the same if there's no atmosphere. A heavy thing might fall slower if it's more spread out, otherwise putting on a parachute would make you fall faster.. As Galileo pointed out, it doesn't even make sense. If you tie two bowling balls together with a string, does that make them one ball twice as big? Do they follow Aristotle's law and fall twice as fast? In other words, Aristotle's predictions depend on name-calling, i.e. your choice of what to call an "object". Nature doesn't care what names we call it. We need laws, like Einstein's, that make consistent predictions regardless of naming choices.

Mike W.


(published on 08/14/2016)

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