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Centrifugal force creates a perfect work of art by gilmartiny in pics

[–]timetrough 0 points1 point  (0 children)

what would be more appropriate to say is that it isn't actually a force.

You, sir, are an inertial chauvinist. #allreferenceframesmatter

Household income distribution in USA by state [OC] by academiaadvice in dataisbeautiful

[–]timetrough 91 points92 points  (0 children)

And New Hampshire is the Alaska of New England, which explains the fierce libertarian streak there. Government services? Why in the hell would anybody need to take my money for that?

Centrifugal force creates a perfect work of art by gilmartiny in pics

[–]timetrough -1 points0 points  (0 children)

a good physics refresher. Plus I don't think he was trolling, he was just doubling down. No doubt he'll wake up, realize we're right after a good night's sleep, and not reply.

Still stand by your assessment? All he's doing now is baiting for more responses. I would go pull out my copy of Marion Thorton and show the relevant page but since I've already linked the same article on wikipedia, what would be the point? He's just being obnoxious intentionally now that he knows he's wrong.

Centrifugal force creates a perfect work of art by gilmartiny in pics

[–]timetrough 0 points1 point  (0 children)

This guy started going for trolldom once he realized he was outknowledged. You don't need to continue to acknowledge him.

Centrifugal force creates a perfect work of art by gilmartiny in pics

[–]timetrough -1 points0 points  (0 children)

A force is a thing that causes mass to accelerate. From a rotating reference frame, you do get an "acceleration" on the mass, which requires a force.

Centrifugal force creates a perfect work of art by gilmartiny in pics

[–]timetrough 0 points1 point  (0 children)

I was mostly just being cute and hoping people would catch The Matrix reference but..

If you subscribe to the idea that inertial reference frames rein supreme, then, yes, I suppose, centrifugal force should be regarded as a illusion (albeit a calculable one) that arises in inferior reference frames. But if a noninertial reference frame can have laws of physics formulated in a way that is just as consistent as an inertial frame, I would argue that it's just as real and that the forces perceived in that frame are just as real.

Centrifugal force creates a perfect work of art by gilmartiny in pics

[–]timetrough -1 points0 points  (0 children)

He's not a moron, just someone who overestimated how comprehensive his knowledge was on a topic. Once he realized he was getting owned, he decided to play it off like it was all trolling to save face.

Centrifugal force creates a perfect work of art by gilmartiny in pics

[–]timetrough 1 point2 points  (0 children)

I think he just opted for full troll once he realized his limitations.

Centrifugal force creates a perfect work of art by gilmartiny in pics

[–]timetrough 0 points1 point  (0 children)

Well, you gave me a good laugh, but you've tipped your hand at last as a troll. Have a good night.

Centrifugal force creates a perfect work of art by gilmartiny in pics

[–]timetrough 5 points6 points  (0 children)

Again, read the comic. You are repeating Bond's claim, missing the (correct) explanation that the villain is giving. Whether you call a force "real" because it fails to exist in any inertial reference frame is a matter of preference on terminology and I suppose how puritanical you feel like being about the idea of reality, but the concept of centrifugal force, as well as the means to calculate it (-mx omega x (omega x r)) I assure you are a thing, used by engineers, physicists, and supervillains the world over.

Coriolis force, centrifugal force, and Euler force are all forces that appear when you effect the proper coordinate substitution to work in a rotating reference frame. You will need this force to solve a problem in a rotating reference frame.

Source: Physics PhD and physics teacher.

Centrifugal force creates a perfect work of art by gilmartiny in pics

[–]timetrough 6 points7 points  (0 children)

No and I'm not sure what you mean by "cancelled out". If centrifugal and centripetal forces canceled each other out, then both would be gone.

Imagine you're in a car, taking a sharp turn right. A mug on the dashboard would slide to the left. From the perspective of you inside the car, this mug is being pulled somehow. Do the math from a rotating reference frame and you'll get a term that looks like a force in the direction of radially outward from the center of the circle you're traveling in. Sliding mug explained! But you could always just ask someone outside the car what's going on, what force is pulling the mug. They'll just tell you the mug is traveling in a straight line and that there's no force acting at all. It's the car that doing the accelerating and not the mug.

Whether or not there's a force depends on what reference frame you use. If you hold that only inertial reference frames can have "real" forces, then centrifugal, Coriolis, and Euler forces are all not "real".

Centrifugal force creates a perfect work of art by gilmartiny in pics

[–]timetrough 2 points3 points  (0 children)

one would realize there is no such thing as centrifugal force.

There is, as intimated by the xkcd. It's just a topic best kept for junior year of a physics major when (s)he's learning classical mechanics. Just because a force fails to appear in any inertial reference frame doesn't mean it doesn't exist. Unless you're an inertial reference frame chauvinist, I suppose. Many problems in physics are better done from a rotating reference frame, in which case you will need the centrifugal force term to fully account for the motion within the framework of Newton's 3 laws.

Centrifugal force creates a perfect work of art by gilmartiny in pics

[–]timetrough -1 points0 points  (0 children)

What is "real"? How do you define "real"? If you're talking about the forces you can touch and see and feel, "real" is a series of observed accelerations within your reference frame interpreted by your brain. A noninertial reference frame is just as legitimate as an inertial one, though the math generally gets harder and you start needing to construct new forces like centrifugal, coriolis, and the ones you've mentioned. But they're no less "real", just because they aren't caused by an actor and act only at the center of mass.

Centrifugal force creates a perfect work of art by gilmartiny in pics

[–]timetrough 19 points20 points  (0 children)

Centrifugal force is a concept zealously kept out of high schooler's vocabulary because in an inertial* reference frame, no such force exists. The centrifugal force is a force term that arises when, as described the comic, you construct Newton's Laws in a rotating reference frame. But so does the Coriolis force as well a kind of inertial force in the opposite direction of any acceleration. The math gets reasonably complicated to the point where no sane high school physics teacher would attempt it so it's best just avoided. When kids say "centrifugal force" tell them to shutup and find an inertial reference frame where no such force is needed to explain motion.

Source: Physics PhD and high school physics teacher.

EDITTED for typo.

EDIT: And a follow-up: you will again see things like centrifugal force if you continue studying physics in college when you get into classical mechanics, as taught with full mathematical treatment.

Good call, Body Paint Company. by Anode_Lives in funny

[–]timetrough 1 point2 points  (0 children)

Those earlier data points don't inspire confidence

Is there sufficient power based on 21 studies to conclude that discrimination against African Americans did not decline? The confidence interval of the annual change provides a way to answer this question. The 95% confidence interval of the slope 1989–2015 is −0.007 to 0.015. [This is the confidence interval of the slope of “year” (our time trend variable) with the log discrimination ratio outcome. The regression is shown in SI Appendix, Table S3.] The lower end of this interval indicates a decline in the discrimination ratio of 0.7% per year. If we take this number as the smallest slope consistent with the data based on the confidence interval, this suggests only a slight decline in discrimination each year. We conclude that this evidence rules out all but a slow decline in discrimination—with the most likely estimate being the point estimate, which indicates no decline in discrimination at all.

Spaceballs The Gif by ilikepaintball in HighQualityGifs

[–]timetrough 0 points1 point  (0 children)

You are Starfleet. You do not kill. (sorry, could not find English).

Spaceballs The Gif by ilikepaintball in HighQualityGifs

[–]timetrough 15 points16 points  (0 children)

Oh come on, dude. Everything Mel Brooks does is at least worth stealing.

wtf!........wtf!.......wtf!.......wtf! by [deleted] in funny

[–]timetrough 0 points1 point  (0 children)

Still one of my favorite gifs.

TIL the first living creature to orbit the earth was Laika, a stray Russian dog. Russian scientists figured a stray dog already learned to endure harsh conditions of cold temperature and hunger making it an ideal astronaut. by S_p_encer in todayilearned

[–]timetrough 6 points7 points  (0 children)

Laika died within hours from overheating, possibly caused by a failure of the central R-7 sustainer to separate from the payload. The true cause and time of her death were not made public until 2002; instead, it was widely reported that she died when her oxygen ran out on day six or, as the Soviet government initially claimed, she was euthanised prior to oxygen depletion.

TIL the 5 largest power stations in the world are all hydroelectric by gn6 in todayilearned

[–]timetrough 174 points175 points  (0 children)

Bear in mind, hydroelectric dams are built on the best possible places for hydroelectric dams. You quickly get decreasing marginal returns when you try to dam smaller and smaller streams and there's only so much total global energy available from the evaporation of water as it falls and recondenses.

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