What's Going on in The Turntable Paradox?
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- Опубліковано 17 жов 2024
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I like the line on the table so we can visually see how fast the table is spinning. Very nice touch
and we also know it's spinning
Wait... AN ACTUAL COMMENT!?
It would be more efficient, if not eye-pleasing to place a big dot on the turntable near the perimeter but at a fair distance. It would give you better judgement of the speed without blurring for a higher speed
This is how you know someone is smart. ONE is asking, "Why does this happen?"
The OTHER is trying to launch the ball to hit someone's junk.
Meanwhile I'm getting hit in the junk and going "why the hell did that happen?"
@@bobthegamingtaco6073lol
@@bobthegamingtaco6073AFTER moaning in agony
Who is the smart one ?
@@redstocat5455the one standing at an angle so as to not get hit in the junk. 🫣
Oh how the tables have turned
Is this an experiment to see which version of the quote gets the most likes or something?
😂😂😂
Still turning pretty quickly
Am I the only one seeing the same comment as earlier?
Well, not at one point is the point of contact that it’s kind of just the same
“Well well well… how the turntables… turn” -Michael Scott
Just the comment i was searching for😂
Or....do they???
*Dun Duun. Da da da ba ba ba ba Da ba*
Ah just what I was looking for.
@@thebelmont1995Vaauce
😂😂😂😂😂😂😂😂
When you get the ball up to speed, static friction is bypassed, allowing it to spin in place. When on a surface with friction, more force is needed to move an object from rest.
I would love to have as a permanent decoration just a billiards ball forever on a turntable, a tensegrity structure, and a water feature in Laminar flow
None of those things are expensive, so just go get them!
@@GamezGuru1Unless they want a custom decoration that integrate all of these features arranged in an artistic manner.
@@Nerdnumberone no u wont get a simple billiard ball set up for cheap
would haave to do diy only
@@Nerdnumberone As one that engages in the visual arts I know what I must do! 🫡
@@GamezGuru1yes!
"The ball just sits there, Why is that?"
Me: Cause its a good boy?
this is the reason I was crappy student???!!!
Good girl even
Sit. Stay. Clever girl 🦖
@@vapormissileis that a Jurassic Park reference
@@ReinigenDieWelt oh yeah
"The ball only knows about this one point contact."
Because it knows where it isn't.
The ball is eepy
underrated
The ball knows where it is at all times. It knows this because it knows where it isn't. By subtracting where it is from where it isn't, or where it isn't from where it is (whichever is greater), it obtains a difference, or deviation. The guidance subsystem uses deviations to generate corrective commands to drive the ball from a position where it is to a position where it isn't, and arriving at a position where it wasn't, it now is. Consequently, the position where it is, is now the position that it wasn't, and it follows that the position that it was, is now the position that it isn't.
In the event that the position that it is in is not the position that it wasn't, the system has acquired a variation, the variation being the difference between where the ball is, and where it wasn't. If variation is considered to be a significant factor, it too may be corrected by the GEA. However, the ball must also know where it was.
The ball guidance computer scenario works as follows. Because a variation has modified some of the information the ball has obtained, it is not sure just where it is. However, it is sure where it isn't, within reason, and it knows where it was. It now subtracts where it should be from where it wasn't, or vice-versa, and by differentiating this from the algebraic sum of where it shouldn't be, and where it was, it is able to obtain the deviation and its variation, which is called error.
I friggin love this track!
... the ball knows too much!
The one point of contact isn't actually a point but a very small area. The part of the area closest to the edge is moving slightly faster than the part furthest so we'd expect the ball to gradually spiral off the turntable. This is the same coriolis affect that drives the world's weather.
Perhaps your imagination "affected" this effect.?
The Turntable is FLAT and level not spherical or tilted and Coriolis is an optical illusion of objects travelling in one FRAME appearing to deviate or curve away from an observer MOVING in a different reference FRAME. And the ball appears to be spinning on the spot.
How does this little whirly pool "ball" confirm YOUR big whirled ball weather CLAIM?
@@AV036 The term is "non adhesive elastic contact" and there is an entire applied physics topic devoted to it. I don't claim anything, you might read a bit about the work of Heinrich Hertz.
@@johnbidwell2393 OK "CLAIM" yes or no in plain English. Q. Is NASA lying to YOU?
@@AV036 Ah. You're a flat Earther. Cya
@@AV036it's like you opened your mouth and a truckload of stupid fell out.
The ball _will_ eventually fall off. This is because there is no point of contact, but a very small circular contact patch, one side of which is moving minutely faster than the other.
To the ball it's the same as rolling down a hill! Neat to see it reach a sort of equilibrium
Not really, when a ball is rolling down the hill it is accelerating downwards.
It’s actually more akin to spinning in zero gravity, there is no net force acting on it.
Exactly!
For the ball its like rolling on a threadmill
639 likes for a COMPLETELY wrong statement. Wow UA-cam is dumb...
@@yesno7889 Would only accelerate until it hits terminal velocity. Then you would get something just(ish) like this.
That last demonstration makes me think of all the times my physics teacher said "centrifugal force isn't a real force".
Well it’s not,
Centrifugal force is just the result of inertia and reference frames, it is not a force in and of itself.
Think of a car, when you turn you FEEL a force pushing you around, but there is none. It is just your inertia and the car changing direction.
It’s not a force but a result
@@CMT_Crabbles One of the best explanations I've ever seen. Nice job.
Well don't we think it should be renamed to centripetal result not force like a real one like gravity but then i expect someone will say even gravity is not a real force due to relativity
@@MrEthanhines Not relativity, bending of space-time. It's the only way that can explain how the gravity well of a black hole (or any other high mass object) can affect a massless particle (light).
I only took one thing from this…”the ball only knows…” balls are sentient now
Anthropomorphism is a strong human instinct and can be useful in explanation. Even if everything is governed by natural forces, we attribute a will.
Gave me flashbacks to when kids were confused how a mirror “knew” what was in the room…
How does it know?
@@quietwarrior4 it uses its ball brain to know
The ball "knows".
Yes it does
I can explain it… the ball becomes offended that you’re trying to make it dizzy so it throws a tantrum and refuses to move…
the camera shots were great in this, on top of the awesome demonstration. great as always, prof mould !!
Oh how the turns have tabled
Is this an experiment to see which version of the quote gets the most likes or something?
@@kallethoren Dude yes. Exactly
So far the other one is winning
@@kallethoren I mean the joke isn't that bad, right?
@@YourMothersFavouriteTerminal I respect the experiment and apologise if I have rendered the results inconclusive by interfering :)
@@kallethoren I mean statistics show that less than 40% of people open replies so no biggie)))
Part of me was hoping you'd dip the ball in paint or something so we could see the trail it makes in the first example. Its movement looked like it had a pattern to it.
It was slow the movement.
The table is definitely putting a circular motion on the ball, its not being spun in one direction
So the table has to be putting enough spin on the ball to counteract centripetal force, which is also why it has to be completely accelerated up to the table speed before letting go
Mabey you're observing something and simply stating what I have tried to define in the comments, I can't tell by your statement. If you swing a bucket on a rope, Centrifugal force pulls it outwards, the rope exerts centripetal force keeping it from flying away. Both are being generated here gyroscopically. See my comment and tell me if it makes sense.😊
Nope, the ball is not experiencing centripetal force at all. This is actually a really cool demonstration of how that works!
The reason for the slight movements is the inconsistent surface of the ball, which makes the friction forces different on different parts of the ball as it spins
"the ball only knows..." ☠️☠️
It’s only a matter of time before it knows how to launch the nukes.📡
"the ball only knows about one point of contact" GOD I love casual anthropomorphization in science. Stuff like "the atoms do NOT enjoy this"
I genuinely love it, it's such a good way to explain stuff. /positive
Feels more personal to that!
Is it a bad thing?
@@michaelric3540 he's torturing matter!
It’s a terrible way to explain stuff and unnecessarily creates the assumption of agency when there is none. You’re actually making it more confusing when you obfuscate with anthropomorphisization.
@@jimmypad5501 I agree. Most of the world still thinks photons are just waiting for you to look the other way before they act up 😂
somehow it reminds about spinning motion of planets and orbits of space bodies
Yeah me too or frame dragging
The universe is a negative bubble.
@@troywhite6039 we literally don't know the shape of the universe
@@bigboy-gw8me Conspiracy nuts know everything about any topic they learn about, instantly. Even if it's just something one guy told them, they absolutely know it's a fact.
@@bigboy-gw8medoes the universe even have a shape?
That's really neat! Thank you for showing me this today 😊!
Perpetual motion finally
You gotta give it to him, he spun that table for literal ages non-stop just to be able to record the ball falling off
The guy ignored magnus effect. That is why the ball is in one position.
@@Derederi correct me if I'm wrong, but isn't the Magnus effect due to vortexes behind a spinning ball? I feel like the ball isn't moving fast enough to generate enough turbulence to move it's weight, but even if it was, it's probably pretty negligible compared to friction.
@@Derederibut it isn't moving " through " the air
somewhere _very close_ to (if not exactly) half the radius of the turntable is where all the forces on the ball are perfectly evened out and the ball will not move!
too close to center and it follows an elliptical "orbit" until it is flung out
too far and the ball is flung out immediately
i imagine this is involved in the introduction to astrophysics :)
Ok... thats makes sense and is also a fascinating way to describe stable orbits around a planet or star.
How can the ball know how big the disk is?
@@trucid2
the rotational speed of the disk gets faster the further the ball is from the center.
the outside is moving faster than the inside, so the ball experiences more forces as it gets farther from the center.
honestly, when i said that half the radius was the point of equilibrium, that was a rough guess. the weight/density/friction of the ball are major factors. im not a mathematician or physicist or anything. i just kinda remember the broad lessons from my high school math & science classes lol.
@@trucid2 I dont know whether the initial comment is actually correct, but I agree, that it sounds quite senseful. While the angular velocity on a rotating plate is the same in all spots, the translational velocity isnt. It grows proportional to the radius. The ball doesnt know how big the platter is, all it feels, as was said in the short, is the velocity at its touching point. Same goes for planets and stars only feeling the gravitational pull at their distance relative to the other object, which in turn is squared antiproportional.
@@Irate_Beau It seems you were slightly faster :D
I love physics, and your videos are relaxing.
I'm studying rotation in general and rotational kinetic energy in particular in this year's cirriculum (senior in highschool), and I was struggling with the concept and sometimes I would have questions with a very similar scenario and you have no idea how much this helped me. Thanks ❤
This is an amazing experiment.
More than you can imagine.
hence... amazing
On a record player, there is an anti-skating force. It’s generally a very small weight pulling in the opposite direction, pulling the needle toward the center with the same force that centrifugal force is pulling it toward the edge. Some use a weight on a string, others have an internal spring, and some have a magnet to supply the force. But my point is it’s very small, it takes very little to keep the needle centered in the groove. Even if you don’t have it, the record will play, it’s just more prone to skipping. And the force is stronger toward the edge, and lesser towards the center, just like in his experiment.
It's very simple.
Objects in motion want to stay in motion. Setting it in the center never allows the ball to reach an equilibrium between the moving point of contact and the need to maintain its current direction of motion. It's definitely trying though because you see the ball spin fast and then slow in an oscillating manner. But before it has a chance to find equilibrium centrifugal force overtakes the ball once it has wandered far enough away at the center. Placing the ball at the outskirts just puts the ball directly into a centrifugal situation. However if you hold it so that it spins in place close enough to the center you give it the time it needs to find equilibrium and so when you let go it wants to remain in that motion state.
The engineer in me is curious as to what orbit away from the center of the turntable provides the most stable point for the ball to stay in place. Like with most forces it can't maintain equilibrium forever and either wander towards the center of the turntable before falling off or wander out and fall off that way.
I'm also curious if this plays a part in how bicycles stay upright. 🤔
Let us know if you found the ideal radius. Id say further out is better
TIL that I think you mean "centrifugal result". Scroll back in the comments for an excellent explanation about inertia and reference frames from another viewer.
The ball's gyroscopic force is greater than the centrifugal force applied on the ball. Eventually air and surface resistant inconsistencies will have an effect on the ball and cause the ball to leave the table.
And what if you put a teeny tiny bicycle on the turntable, instead of a billiard ball?
@@rodschmidt8952 I think it would ride along for a while correcting itself not because of the wheels spinning mind you but because it's designed to stear itself right if as it falls. (Source: I saw some other video about this like 2 days ago)
Steve, I love your content
Instructions unclear. Got a testicular torsion.
I need a mini version of this
Moon be like damn bro
wow, how the turntables (I hate myself for this)
Is this how Celestial Bodies stay in Orbit of one another?
Good question! I do wonder how they hold in place.
All objects moving in circular motion have a certain force being applied to them called centripetal force, that pulls them towards the center of rotation. This force prevents them from flying off. The centripetal force in the case of celestial bodies is the force of gravity between them. When they are moving around each other at just the right speed, they are able to move in a circular path, and are held from flying away tangentially by the forces of gravity. If gravity were to suddenly disappear, all planets would move in a direction perpendicular to the direction of the center of rotation (a tangent).
This is an excellent way of demonstrating how centripetal and centrifugal forces work, and why they exist. Just using that setup, you're able each distinct element of the interaction, and show how the way that those elements intersect determines the outcome that you end up with. If a person remembered enough from their trig clases, a handful of basic forces (like friction) had already been discussed, theat person would able to describe an equation that explains and predicts the events (in broad terms, of course).
Your delivery of "The BARGAIN! (shop)" is genuinely hilarious. Nicely done.
Oh how the turned have tables
Oh how the turntables
How oh table turned have
The how oh turned tables have
have the Oh tables turned how
Make a video on which you are finding out mistakes in electroboom's videos
So, the only question remaining is, where do i put the cue ball so that i can make this shot go into a corner pocket??
Kind of reminds me how precise we get with orbital satellites and space stations. They are still "falling" but moving at such speeds with no air resistance that it would take ages to fall back into the atmosphere
This happened to my ball
Es muy interesante pero me cuesta ver las fuer,as combinadas implicadas.
Creo intuir una centrifuga y una giroscópica contraria pero puede que haya otros efectos incluídos.
What happens if you apply this to something larger...
Say... a planet orbiting a star.
Well, in that case, there's no point of contact so the planet should not stay in place.
Thats more like a yoyo nd a ball falling down, the yoyo is spinning with the string attached to the ball, basically pulling the ball as it spins, with no point of contact the ball wants to be pulled and then fall away, but the string (gravity, in the sense of planetary scale) keeps it a certain distance before it cant go any further
It gets, a whole lot more complicated then that, qnd im not q scientist.
I like your ball from the 3-in-ONE Tournament Table.
I feel like holding the ball in place as it spins up imparts it with the kinetic energy of the table, matching it in velocity and motion, so it stays in place. It matches, and a sphere is about perfect for this.
Just dropping it onto the moving table requires the ball to over come inertial forces and slowly try to gather that energy to match the table's motion, which it doesn't have enough time to do before being thrown off.
Finally, starting from the middle. I think the major factor for it being thrown off is that it's not precisely in the center, so as it starts moving on the table, it's constantly trying to change direction as evident in the video, so it doesn't get time to build up that matching speed and direction in harmony with the table. Eventually, the centrifugal force throws it off when there's no more room to self-correct.
We have an exhibit that showed this off in my local science museum! It’s disks instead of balls, and visitors can hold them over the table until they get up to speed, let go, and watch them roll. I always thought it was the coolest thing as a kid
This is how ball bearings work!!! Thank you for the perfect demonstration!!!
The footage of the ball rolling perfectly on the turntable. Reminds me of the times when I would play legend of Zelda majora‘s mask, and I would just sit there and roll around as Goron link.
If you ever think something is a paradox, it is purely because you don't understand what's going on.
Beautiful explanation.
So the ball has to know what to do, i see
Now I have to go look for an old turntable to verify this experiment.
“Blissfully unaware sphere” is what I aspire to be in life
The ball only knows one point of contact.
friction would pull the ball into a wider orbit, increasing its acceleration, which would pull it further, but the gyroscopic effect would cause it to be angled to roll slightly towards the center, and the two cancel out
A question I never knew I needed answered, thank you very much for educating me.
Love these, please keep them coming
Crazy stuff even when u can see it in person. Just freaking magic.
I like these never too late to learn something new huh
This was really cool and fun to watch. I think you are asking the universe the correct questions...
That initial movement was more interesting than the last one
Same reason that objects in space act the way they do around other bigger objects iirc.
It would be cool to see several balls spinning like that at different distances from center at the same time.
The rotation speeds are matching like those gears that form a 90 and rotate.
It's like the ball is rolling in one direction. One point of contact giveing the same input.
Imagine the disc rolling vertically. Or two gears rolling against each other.
The first demostration shows the ball accelerating and decelerating a lot. That's also very strange and interesting.
this begs for a really interesting question. what happens if the disk is very slightly curved so the ball, once it gets up to speed, is sliding towards the center?
does it overcorrect and move beyond that center point where the disk is technically moving in the opposite direction causing the ball to fly off, or does it stay at the center? if it stays at the center, would it lose speed until it flies off?
or would it move outwards in the direction it came from until it stabilizes somewhere off center?
also as a side note what would happen if the disk is curved downwards causing the ball to move towards the edge? that would make the ball spin faster right? if it spins faster, is still gonna fall off?
is the friction between the ball and the contact point the only thing stopping the ball from sliding off the downwards curved disk?
This would be really cool as the basis of a modern art piece
With it stationary but rolling, you have given it angular momentum... i think thats what its called. Much like the wheels on a motorcycle or bike wheels keeping the bike upright. If you change the angle the wheel spins, there is a great deal of resistance, because you are changing the direction of the momentum. Same principle. For the ball to move in or out on the turntable, something has to apply force to change the direction of its existing momentum. Idk if that makes sense. Its been decades since I've studied physics
The ball only knows of one point of contact.
"The ball only onows about that one point of contact?"
Excuse me! The ball knows things?
If anything the air resistance probably even helps it to stay in place
That number 11 pool ball was a happy sphere at the end. ☺️
this is what we can do for indoor skiing!
It's like a 2D representation of being in orbit
HOLY SHIT
Oh
You do this on my turntable. All I know is that you get a clip behind the ear for touching dad's stereo. 😂
This would make a cool desk toy
Ohhhh so the ball is conscious. It only "knows" about the one point of contact. Interesting.
As seen on conveyor in market, when you put bottle lying at the right angle.
I would guess that if the ball and round spinning surface are moving at the same speed and in the same direction, it would be the point of least resistance to stay where it is. As the surface is round and spinning, the only point truly moving in that one direction and that precise speed would be directly where the ball is. If the ball kept going with tbe surface, the surface would change direction. The ball, internally, has centrifugal forces being applied that resist changes in direction. Thus, moving along with the surface would create a form of resistance.
Similarly, moving in or out from the center creates two points of resistance. One is that as the ball moves towards the center, fhe surface moves slower, and as it moves to the outside, it moves faster. On top of that, the ball would need to roll in a direction perpendicular to the one it is currently spinning in. This would go in direct opposition to the centrifugal forces in the ball. This would create high levels of resistance to a change in position.
Bro is talking like the ball just decided to stay rolling in one spot😂
Basically, because it’s spinning at the same speed as the outside forces movement, it’s like neither are moving at all
That’s what I call an infinite spin.
tusk! spin his balls
I assume that a billiard ball works best as it's rigid and perfectly spherical at all times. A softer ball might have more contact area with the turntable and would pick up some extra force, pushing it outwards.
I’m so happy that someone finally figured out the answer to this dilemma!
This is making me think of that dragon ball commercial bumper where goku and oolong spin an umbrella to keep the dragon balls up.
my dumb ass in ceramics forgetting to pick up my sponge before turning the wheel back on
It would be interesting to see if the air creates resistance in a scenario where both the ball and the turntable are perfectly smooth (glass table and polished cue ball) and if it would slide off even after hours/days.
Bros got some balls doing it with a poolball 💀
There are so many cool physics interactions that can be scaled down and simplified it is wild
my kids love playing this game on my pottery kickwheel.
I’ve wait 3 years to say this
Best sequel ever made < : D
( Why did you have to hurt me so much )
the most interesting thing for me is that in presence of some energy loss the spinning ball eventually goes towards the center - the place where the rotation speed is zero!
“the ball only knows about that one point of contact” and “there’s very little wind resistance” those two statements made it super easy to wrap my head around this ❤
The first spinning ball reminds me of the spinning objects such as spanners on the ISS, where they keep switching directions
The ball knows about single point of contact, it must be sentient :D
well done you have justdemonstrated the gyroscopic principle