You’re over-qualified! I have a babysitter’s course certificate that I got when I was 14? 15?..!
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I would weigh in, but rotational kinematics is the part of my physics course that kicked my butt. That stuff is wild.
I don’t want to argue about aerodynamics with you, and I’m not, but to say a brick on a string has as much aerodynamics as a yo-yo is extremely vague, and possibly irrelevant, depending on what you meant by that.
Anyway I specifically mentioned a yo-yo is not a simple falling body because of its rotational inertia, so the mechanics are more complicated. Maybe I wasn’t clear with the wording.
Unless it’s in physics or mathematics that’s not a very compelling argument. Technically, it’s not any argument.
I studied a lot of physics in college but it was a long time ago. Aerodynamic forces may indeed be insignificant for yo-yos, but I am slow to leap to such conclusions without evidence, and I haven’t seen any, nor am I likely to see any since physicists tend to have better things to do than set up precise laboratory experiments studying the mechanics of yo-yos and what makes them “floaty,” whatever the hell that even means.
And there’s no need to call everyone kids. Regardless of who is right in this discussion, if there even is a “right” in such a subjective debate, calling someone a kid is rather condescending (and in many cases not accurate).
Sorry, I should’ve been more specific. My degree is in aeronautical engineering with a specialty in fluid mechanics and aerodynamics. And I stand by my comment about a brick on a string.
Overall floaty is generally applied to yoyos that are easy to move
All right, I suppose I’ll take your word for it in the absence of contravening evidence, since an aeronautical engineer should know quite a lot about aerodynamics. My degree is in math (physics minor). I took some advanced analytical mechanics but probably not as much as you did.
I just wasn’t sure what you meant by the comment about the brick on a string. Linguistically, what does it mean for X to have as much aerodynamics as Y? I’m guessing you meant that aerodynamic forces apply equally to a fixed body on a string and a body rotating about an axis on a string. I don’t necessarily disagree with that, but surely the cross-sectional area of a yo-yo in large part determines the drag force? Are you saying that the cross-sectional areas of arbitrary yo-yos are not different enough to affect their respective drag forces in a readily apparent way? That does seem likely–I’m just an extremely skeptical person and don’t like forming conclusions one way or the other without hard evidence.
What he meant when he said that is that aerodynamics is as irrelevant to yoyos as it is to a falling brick. It hardly affects it at all in regards to normal yoyo play.
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It’s not THAT irrelevant. I have a yoyo with holes In it (not the breathe concept) but it spins shorter than most of my other yoyos, I can even hear the air resistance, it sounds like a fan. However with yoyos that don’t have holes in them, air resistance has some affect. It wont just happen when the yoyo is spinning and not moving around, air resistance has little to no affect then. However when you are doing tricks, especially speed tricks, a Phenom is going to cut through the air faster than a hitman pro. (sorry for the old yoyo comparison)
when you are lifting weights, the distance between the weights on either side of a dumbbell does not determine how hard it is to lift it. A 100 lb. dumbbell is 100 lbs.
It’s the same with yoyos, a 65g yoyo is 65g.
I see your point, and it is very valid. Cross-sectional area does determine the drag. The problem is that yoyos do not have a very large cross-section, and they somewhat heavy for their size. Yes, there is drag on the yoyo, just not enough for it to matter that much, even at hiroyuki speeds.
The holes in that yoyo would cause extra air resistence.
Also, I disagree that a
[quote=“DKiminator,post:68,topic:67208”]
.
What I think is going on is that our eyes play tricks on us. When we see a large yoyo, we naturally expect it to be heavy, but if it isn’t, we say that it is “floaty”.
In my opinion I think floaty-ness is basically the string presence to weight ratio. If a yoyo is 65 grams+ and feels light it is floaty while a yoyo is 64 grams and under would just be considered lightweight and not floaty imo. Because I view float as the lack of presence on the string but idk.
I’ve honestly never thought ANY yoyo was “floaty”
it’s just not a term that comes to mind when I am playing.
I don’t do a combo and think, “boy, I bet this thing will levitate for me!”
If a yoyo is getting good air/hang-time on a trick, that’s because I popped it up in a way… that it’s gonna get good air/hang-time.
:
Now that I’m done being a butt…
To get back to the Original Topic…
Tech is something I love to do, but if I’m completely honest, I don’t think tech is “difficult” 90% of the time.
Because 90% of the time, tech is ONLY, underpasses, somersaults, barrel-rolls, hops, pops, and undercuts. (with a slack or two for “variety”) - & 7 elements do not comprise all of yoyoing! ;D
To me, any combo that has only those elements is a prime candidate for the term, “Generitech.”
People like Zach, Chuck, Zammy, Nehemiah, Anthony R, Yuuki, Ayumu, Shinnosuke, Spencer B, Seth P, Grant J, Rodrigo Pires, Guy Wright, & Mark Allen have all been great about not just bludgeoning those 7 things to death and exploring ways to keep tricks extremely technical and complex, without losing an ability to get a sense of the scope of the tricks that they’re doing. I can watch them and feel “lost” in my ability to keep up skillwise… but I never feel “lost” in not keeping track of the flow. Each movement feels fresh, and new, and completely distinct from everything else that I just saw that player do.
Conversely, a lot of tech that only has the 7 elements listed above, will be extremely fast, dense, complex, but it really all kinda looks the same. And each time I watch a trick, it feels just like the trick before it - even if all the mounts and transitions are different - they’re really all kinda the same.
Thank you! This is a great answer to my question.
Did you even read my reply from before?
Yes. It was also good, but this topic had gotten so clouded. I was happy to see another on topic post.
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“String presence to weight ratio” sounds like a quantitative definition, but what is “string presence”?
Float is just a super vague concept. Also, and this is not directed at you, I think in general rotational dynamics do affect aerodynamics. I played a lot of ping pong yesterday and the ball’s mid-air trajectory depends largely on its rotational direction and speed. Its “hang time” or floatiness depends on how hard it’s hit but also on the amount of backspin. Large amounts of backspin create lift. This is true for heavier objects like golf balls as well. Maybe the rotational speed does not affect the aerodynamics of a yo-yo significantly, but this is very hard to test.
Model experiment: Use two yo-yos, a Draupnir and an E=MC^2. Stand on top of the empire state building. Throw both yo-yos at the same speed and toss them over the edge. Have someone at the bottom time the impact for each yo-yo. 
Just reading this makes me cringe
I would define float as the ratio of angular momentum(or rotational inertia, depending on rim weight, diameter and also total weight) to total weight.
A rotating object is harder to accelerate than one at rest. When in the air and the strings loosened, the yoyos acceleration is only provided by gravity which is weak enough for angular momentum to play a role.
A spinning draupnir falls quicker than a non-spinning one, and the difference in falling speed between 2 draupnirs, one spinning and one not, is likely greater than that difference between two e=mc2s.
Pushed acceleration is roughly inversely proportional to weight*angular momentum. The phenom, for example, is fast, but ive yet to hear anyone call it floaty.
I don’t think the physics are being correctly applied above. Just for the record.
A spinning Draupnir and a non-spinning one will hit the ground at roughly the same time; the incredible scale will actually mean that the non-spinning one is more likely to hit the ground second as it may encounter more air resistance.
Air resistance at the scale during play makes it a non-factor, though.
Did a little more research and turns out that we were both wrong. http://brucedepalma.com/n-machine/spinning-ball-experiment
now which situation is closer to actual yoyoing? lol derp idk Note however, these experiments werent done in vacuum so we still cant rule out air res…
I wasn’t wrong. 
The spinning one is hitting the ground first. However, I was citing the effect of air resistance slowing the one rather than spinning accelerating the other. I still believe this will be the greater factor than the “force greater than G” in the experiment.
Mainly, though, what I was referring to was the predilection of people using physics in yoyo discussions to conflate rotational and linear acceleration and moments of inertia.
In any event, even this “force greater than G” that the experiment refers to is ultimately not what people are noticing when they talk about float. It would take instruments and high speed motion capture to spot even the slightest difference in a controlled experiment, never mind during play. Nah, “float” is about a lot of things, but it’s not about this.