I have a bunch of errand-running to do today, so I will leave you with a Dorky Poll question for entertainment, this time regarding the work of the great Sir Isaac Newton:
We're still dealing with classical physics, here, so superpositions of results are not allowed. Pick one and only one answer.
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I have a thousand things to do today, and blogging isn't high on the list. So here's a dorky poll to pass the time, because it's been a while:
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Inertia! The first and still the best.
It's gotta be #3, if only because it's so frequently misused.
Besides, it's the answer to Arthur Weasley's fondest wish ("to find out how airplanes stay up")!
Inertia, just because it must have been so counter-intuitive at the time.
Action-reaction is the one that is sufficiently non-obvious that the New York Times editorial board got it wrong in the 1920s. They published an editorial against Robert Goddard's rocket research, claiming that rockets couldn't fly in space because "there is nothing to push against." At least they eventually realized they had egg on their face; they published a retraction in July 1969, as Apollo 11 was on its way to the Moon.
check out this article (does not relate to this post)
http://www.csmonitor.com/2009/0820/p09s02-coop.html
F=ma. Because you don't have to be bigger than the other guy if you're fast enough.
The Third Law is the winner in my view. What other law of physics can claim be the cause of so many children suffering brain damage from falling out of grocery carts while simultaneously allowing the insurance industry, with congresssional approval, to avoid payments for monetary damages when the child is injured. Heck, the little signs on the grocery carts don't even have to give credit to Newton. Sir Isaac was robbed, I say, robbed!
N1 and N3 are corollaries of N2.
The first law is from Descartes, the second from Huygens, the third from van Helmont and the law of gravity from Boulliau ;)
My favorite law is undoubtedly Newton's Third, but I refuse to vote for it if it's described as "action-reaction." The law is about force, not "action," something I mentioned to my new students just this morning. Unlike force, "action" is not a clearly defined notion (at least not in the way it's being used here), although it implies motion in people's minds---even though we all know that Newton's Third Law is quite important even in static situations.
And, unlike Newton's First Law, the Third can in no way be considered a corollary of the Second.
I object. Newton's 3 laws are different points of view, but they are ALL conservation of momentum.
Plus, no one remembers his Law of Heating and Cooling much any more (larger the temp difference, the greater the rate at which temps equalize).
The second "law" is really just a definition of the word force. The second and third can be replaced with a single law ma1 = ma2.
Mark Dow: maybe now the second law is more like a definition (written in modern vector notation), but back in Newton's time is was not obvious. i would still call it a law.
This quiz presupposes that (1) Isaac Newton actually came up with these theories and didn't steal them, as maintained in The People's History of Science by Howard Zinn, and (2) that Isaac Newton would consider these "his" laws in the first place.
NS
The first law, precisely because it is NOT a corollary to N2 as asserted @8. The first law tells you how to choose a correct coordinate system. As just one simple example, you have to include fictitious "inertial" forces if you use an earth-fixed coordinate system.
The first law tells you that the first step in solving a problem is to choose an inertial coordinate system and clearly define it before writing any equations.
F = ma is the one you can't get anywhere without, and is incidentally totally awesome.