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While gravity can to a degree obscure this fact, it’s corollary that an object in motion will stay in motion is pretty alien to anyone who has grown up on earth, under the daily affects of atmosphere/friction.
Exactly. People weren’t so much amazed by the fact something wouldn’t move until you moved it, they were much more amazed by mathematical proof that in the vacuum of space objects will just keep moving however you pushed them - it’s an alien idea when all you’ve ever experienced is the opposite on Earth.
This wasn’t at all obvious. Hold a pencil out with your hand. Let go. Did the pencil just stay there in midair?
The fact that things fall because earth imparts an invisible force on everything around us, and that in fact, every massive object imparts that same invisible force on everything else around it, was pretty revolutionary.
It’s hard to overstate how unintuitive this would be to someone who had grown up at that time. Believing that something sufficiently far from earth would just float around and not fall was probably too much for most people at the time.
It’s also a bit incomplete because he also said a object keeps the same speed, even if it’s not zero (not moving). And the speed also has to keep the same direction. This does explain a lot about gravity, orbits etc…
And that’s only the first law, it’s a premise to the other even more helpful laws.
This is Aristotelian physics, wherein you apply effort to an object and then it moves until that effort is used up.
Newtonian physics posits the existence of counter-balancing forces, wherein everything is already in motion and what you experience as movement is just a change in acceleration and direction. The classic “apple falling on my head” story is about Newton questioning why a thing which was not moving would suddenly start moving simply because it was disconnected from its host.
That gets you to his 2nd Law of Motion, wherein a body exerts an equal and opposite force on its surroundings. And a thing that isn’t moving is simply experiencing a countervailing force relative to where it would be moving unimpeded.
It’s a joke man, just laugh and move on.
It’s a bad joke, tho
I upvoted your previous comment, but I wouldn’t say it’s a bad joke. Reductionist humor is still a valid form of humor, even if it doesn’t appeal to you.
So ignore it? Not everybody has the same humor as you
It do be like that sometimes
What about very small rocks?
Churches!
Second time today someone has reminded me of Hitchhiker’s Guide to the Galaxy! In this case the Cathedral of Chalesm that illustrates the dangers of irresponsible time travel:
The cathedral was scheduled for demolition in order to build a new ion factory. However, due to delays in construction and a strict deadline for the start of ion production, the beginning of the project was extended so far back in time that the cathedral ended up never having been built in the first place. As a result, picture postcards of the cathedral suddenly became immensely valuable. And blank.
Not as many people know that he was the father of calculus (along with Gottfried Leibniz who figured it out independently around the same time). That’s really where all the heavy lifting was in elementary mechanics, where by using the laws as something of a base case (especially the 2nd, F=dP/dt), calculus could be used to project an objects future motion. So in a way, it was by calculus that the laws could be shown as accurate in the first place.
I think Kepler deserves some credit too, that dude basically figured out a specific application of calculus in the motion of orbitals before Newton’s and Leibniz’s general calculus even existed.
I think they already knew this, the new thing must have been ditching the “probably”.
