I'm well aware that its different, but you claim its weightless. Well, if it has an atomic weight, then it has one form of weight. And if it has mass, it has another sort of weight. But you've claimed it has NO weight. So I figured I'd better cover all bases here, and see if you were talking atomic weight, not actual weight. Apparently not. So you are saying that helium has no actual weight. And thats wrong.
Um, I guess you haven't figured out that I'm asking stupid questions to see how stupid an answer you will give. See, you think gaseous helium is weightless, and thats just not true.
There are NO forces pushing it farther from the surface of the planet. Its very simple, something heavier is displacing it because that heavier gas is being pulled by gravity, just like helium is. Same theory makes a ship float on water. The ship is less dense than the water by virtue of the fact that its full of air, so it floats on the water.
Yeah, but you seem confused by it. See, you've just said that water vapor (steam) has weight because it water. Yet that water vapor WILL rise through the air, particularly if its heated and is steam. Its the same with helium, which you seem to think acts totally differently as a gas than water does as a gas. If water vapor (gaseous water) has weight, then so does gaseous helium.
I've simply taken your theory about helium gas and applied it to another element(s) as a gas, and shown how your theory doesn't work.
Water vapor and steam are not exactly the same thing. Do you know the difference?
Water vapor disperses through the air and may be considered weightless however, I don't recall many ships sailing in vapor, do you? Helium is actually LIGHTER THAN AIR and that alone makes it different..
LOL, steam usually has liquid water in mechanical suspension and that makes it heavier than air. Put liquid helium on any scale under normal atmospheric conditions and it will have weight. Put helium gas on that scale under the same conditions and it will show nothing at all.
No, you didn't because water vapor can be and is part of the atmosphere and helium is not.
LOL, the fact that you just said this shows that you really don't have a clue.
Wrong.
Weight is a measurement of downward force and if something has no measurable downward force under a set of conditions, then it has no weight under those conditions. That is the difference between weight and mass.
No, what I'm seeing is you spin once again because you got called on your BS and have no other way out. Gaseous helium is not always weightless but on this planet in our atmosphere, it is. Even on the moon, which has no definable atmosphere, the gravitaitional force of the moon cannot hold it to the surface so it is for the most part, weightless there too.
Then why does it rise?
LOL, anf the only way something can be displaced (moved out of the way) is by a force. No force, no movement.
Yep, but the hevier gasses are being pulled harder and their mass is pushing the helium up and away, effectivly negating the force of gravity, (the one force that gives something weight) and if this force is overpowered, the weight must be zero or less.
water by virtue of the fact that
Yep, which makes it buoyant or weightless while it is floating in the water because the water is supplying enough upward force to cancel out the force of gravity. If it could not do that, the ship would sink (fall to the bottom).
No, it has mass but that doesn't mean that it has weight in a given enviornment. If you were to move an object to a place between the earth and the moon where the gravitational pull between the two bodies was equal, what would your mass that always has weight weigh? How about nothing. Did the mass drop to zero in this location, NOPE. Sorry Tom, but you are wrong.
But we do not live in a vacuum Tom. This planet has an atmosphere and its mass and density must be taken into account.
In a vacuum, yea, but we don't live in a vacuum. How much does it weigh out in the open as both a liquid and a gass?
Yes, because then it has a weight (positive downward force).
Yes again, because its downward force (weight) is removed.
Wrong, it has everything to do with weight because weight is not mass. Weight is the measurable net downward force and if this force cannot be measured in a given enviornment, then it has no weight.
But mass and gravity are not the only players. You do know that, right? You must because you keep talking vacuum for the weight of helium.
If it is buoyant, then the downward force of gravity has been matched with an equal and opposite force. Remember that vector addition you were talking about. If the force is cancelled out, then the weight (for that environment must be zero) but hey, feel free to weigh a buoyant object while in its still in its buoyant state and let me know what it is.
What happens to water at 212°F? (Of course, at 14.7 psi here... don't want you getting carried away)
You seem to be caught up in the fact that if you can't measure it, it has no weight. That's false. Again, weight is a measure of gravity acting upon a mass. If the mass doesn't change, and gravity is constant (it was, last I checked.... hang on.... ... yep, constant), then the weight doesn't change. Just because the material in question won't hold still on a scale, doesn't actually mean it's weightless.
So now gravity only acts on those gases that are "part of the atmosphere"? You're saying gravity is prejudiced?
Weight is a measure of gravity on a mass. Period. You're big on definitions - try this one:
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"The force with which a body is attracted to Earth [...] the product of the object's mass and the acceleration of gravity" *
Okay... now start in with the "yeah, but"'s, and the, "downward force"'s, and everything else to deny this simple fact: just because something floats in the atmosphere does NOT mean it's weightless.
Actually, to be entirely correct, this should read as the inverse of the object's acceleration - as an object accelerating at the rate of 1g has no weight... but an object accelerating at the rate of -1g (ie, going against gravity at 32ft./s2), weighs twice as much.
Weight is the application of gravity to a mass. If there's mass, and there's gravity, there's weight. Plain and simple.
Apparently, some of us do... :)
What did I just say? I said, "at 0psi, at 14.7psi, or at 10,000psi - it doesn't matter"... a given mass will always weigh the same, regardless of it's volume, pressure, or temperature.
(Note, in order to not go off on all kinds of wild tangents, I'm deliberately ignoring the factor of acceleration here... for our purposes, all objects being discussed are assumed to be at a constant speed... could be zero, could be mach5 - but we're not going to introduce acceleration into the mix here.... things are complicated enough)
11.25lbs., Tom.... pressure does not change the mass of a gas, only it's volume. Therefore, since mass is constant, and so is gravity (hang on again..... .... yep, still constant), it weighs the same.
No... it has greater density than it's surrounding gas... has nothing to do with weight. It still weighs the same.
Go back to the ice cube example.... why does an ice cube float in a glass of water? Is it weightless? Does gravity somehow stop acting on it because you put it in the glass? Why does the weight of that glass increase when you plop an ice cube in it? It's the exact same principle you're continuing ot argue, and it's absolutely rediculous.
Incredible.... you actually think the gas loses mass because it's allowed to expand...
See definition in previous post. Weight is the measure of the force of gravity exerted upon a given mass.
When it comes to weight, they absolutely are (well, again - setting acceleration aside - but we're not talking about objects in free-fall here). Gary first brought up the idea of a vacuum, to counter your claim that helium didn't weight anything. He suggested weighing a bottle with a vacuum drawn on it, then a bottle full of helium, and note the difference. This was also to dis-prove your assertion that helium had no weight.
The next person to bring up vacuum was YOU... you asked me how much
1000cu.ft. of helium would weigh... I told you 11.25lbs. You asked "in a vacuum, or at 14.7psi?" (as if that would make a difference... IT DOESN'T). I replied that it didn't matter... at 0psi, at 14.7psi, or at
10,000psi... the mass of 1000SCF of helium (and just so we're clear, that's a measure of the AMOUNT of gas that would fill 1000cu.ft. at 14.7psi and
60°F) would ALWAYS weigh 11.25lbs. here on good ol' planet Earth.
Yep - I sure do. The net resultant vector doesn't mean the component vectors don't exist. And also again, just because something isn't exerting a force on a mechanical measuring device, does NOT mean gravity isn't still pulling on it. And, after all, that's what weight is. We just MEASURE it as a downward force, because it's convenient to do so.
You really are like an ostrich with it's head in the sand... "if I can't see them, then can't see me". For the umpteenth time, just because YOU personally can't measure an object's weight by placing it on your bathroom scale and reading it, does NOT mean the object isn't being affected by gravity. And THAT, not your bathroom scale reading, is the scientific definition of weight.... the amount of force exerted upon a given mass by gravity.
LOL, you forgot weight = mass x acceleration of gravity?
You have now announced that NOTHING with mass has weight. Transportation engineers are now scrambling to capitalize on this theory, right?
Just as you cannot measure an aircraft's weight while it is flying/floating, you cannot measure the weight of helium while it is flying/floating. BUT, that does NOT mean it is weightless.
Well, thats two stupid answers. Gaseous helium has weight, since it has mass and will be accelerated by gravity once it is displaced by the heavier atmosphere.
As to no helium on the moon.....
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They seem to thinmk there is one helluva lot of it there.
So a ship on the Atlantic is weightless, because the forces pushing it away from the ocean floor (earth) are greater than the gravity trying to pull it back.
Because the heavier portions of the atmosphere are displacing it. Sorta like I said right here:
The force of gravity is acting on the heavier air, just as it acts on the helium. Sorta like I said right here:
So a ball thrown through the air is weightless?
So they are lying when they refer to a ship so many tons?
Hint: nothing cancels the force of earths gravity except going out beyond the moon to get away from the earth.
Funny... a concept so simple I didn't think to question him on it till you brought it up. I wonder where he thinks atmospheric pressure comes from in the first place? I mean - SOMETHING's gotta weigh something to generate that 14.7 pounds per square inch...
He forgot one basic fact of physics... everything has weight. This basic fact is why man started wondering why birds could fly. There HAD to be a countering force.....
ok no matter how a tried to keep from arguing these i just cant leave this one any longer....
"Helium is weightless on this planet because the forces pushing it away from the surface are greater than gravity trying to pull it back."
that's his statement right????
OK THEN!
go pick up a 75 lb bar bell.....the force you are excerting on the bar bell is exceeding that of gravity. YET your arms will get tired after holding the bar bell for a while......NOW! why would that be??? its weightless right?
You can't ignore acceleration. That's what g is after all!
I think there's some confusion over mass and volume (and density).
A ship would be pretty heavy, yet it [generally] floats on water. Not because it's lighter than the water, but because it weighs less than the volume of water it displaces. Same for a hot air balloon.
The ice cube and water example is a bit more complicated since water has a rather unusual property: It gets more dense as it cools (like most stuff), but then, just as it approaches freezing, it suddenly gets less dense!
Very unusual, but fortunate if you are a fish, since otherwise, rivers would freeze up in winter from the bottom up! There goes the ice fishing season!
That would be due to the fact that your muscles are exerting a force on the bar bell to counter the force of gravity.
......NOW! why would that be??? its weightless right?
In relation to the earth, yes it would but in relation to the person holding it up, not at all because the person holding it up would be supplying the force against gravity.
LOL, it is nothing more than the definition of weight and weightless. If we go by your hard-line definition of weight as the attraction between two separate bodies (gravity), then you have proven yourself wrong on your freefall theory because that force (gravity)exists, free-falling or not. I find that definition of "weight" as meaningless because it serves no purpose, but is good to hide behind when you are afraid to think outside of the box.
Are you now saying that steam is a liquid or are you just spinning because you don't actually know the answer.
Are you now saying that water vapor and liquid water are the same thing?
Really how. Are you now saying that a rought sea is actually vapor, LOL?
Prove it. What is the density and atomic weight of steam?
Who say's it rises? Perhaps some of that rising you see is due to the energy imparted on it from the pressure and temperature but steam does cool off. Helium doesn't depend on it's temperature being greator than that of the surrounding gasses to rise.
No, you just don't understand it or know that you cannot weigh it this way which makes it weightless by definition.
W R O N G!!! Everything has mass but if you were in a point in space where there was no gravity or the force of gravity was negated by another force (perhaps the gravity of another mass), there would be no weight.
I understand that... but what I don't want to get into is how a mass can ACTUALLY be considered weightless- that is, when it's acceleration is exactly that of gravity (ie. falling at 32ft/s2). I also don't want to get into the fact that an object's weight will INCREASE if it's accelerating in the opposite direction of gravity (ie. the shuttle pulling 4+g during liftoff... astronauts weighing 700lbs.). The principles being discussed here are all with the mass at 1g.
But see... now ya made me get into it! :)
And the vast majority of us understand that concept. TBone will claim that the ship is weightless because it's floating...
Well, yes - but it's an easy example to comprehend, and if one had a small kitchen scale, one that's easily reproducable. The fact is that the ice is slightly less dense than the water, therefore it floats, but adding an ice cube to a glass of water sitting on that scale causes the scale's reading to increase. Simply amazing, given how that ice cube is supposed to have no weight when it's floating :)
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