Just out of curiosity, does anyone know whether inflating a tyre with helium would make any difference on the over all performace or if it is even possible. I would think helium is not ‘light enough’ to warrant any difference in weight etc.
Yet the child-like logic that has been bestowed in me by picture books and cartoons lead me to express my curiousity
Hey… put credit where credit is due.
There isn’t enough volume in a uni tire to make any significant difference in its weight. Also, Helium atoms are the second smallest–and are likely to speed their way through the sides of the tube and tire during the course of your ride.
well you did not actually ask the question, you just had a wise crack at why someones uni is so light.
But yes Mr Borgschulze was the inspiration behind this thread.
I think this was discussed a couple of years ago.
My opinion - a tire would not hold enough volume of helium to make any significant difference in weight.
see my response in ‘how heavy is your uni?’ thread
Theoretically, if you had a big enough tire, you could “float” when you hopped…
don think so, it would be completely impossible, your weight plus the weight of the rubber would be impossible for the helium to make up for.
As another poster says, I’d expect the tyre to go flat really quickly. Helium is very good at finding its way out of things - this is why (I think) helium balloons are usually all metal coated. If they’re just rubber, the helium leaks out through the rubber really quickly.
Whilst this is somethings of a stab in the dark I’m thinking that as the helium atoms are less dense and therefore further apart the tyre may compress more when you hop/ride/whatever so more prone to hitting the rim. Probably not enough volume to make a difference but you never know.
Another not-particularly-scientific response: while the idea of helium being small and likely to leak makes sense, my experience with rubber party balloons is that either helium or air will leak through, and I’ve not noticed a significant difference in time between them.
As is seeming quite agreed, the ‘lift’ gained would not be of a useful or even detectable amount. Think how much a helium balloon can lift from the ground? Only a few tens of grams per balloon. I once spent hours at home after going to a fair trying to create equilibrium with a balloon, and all it needed was a small paper ‘basket’ with some extra paper in to fine-tune the weight. Those wacky types who go flying with balloons tied to a chair have thousands of them!
Sam
Permit me to interject;
Helium does diffuse through materials at a faster rate than N2 or O2. The effect is most noticable in rubber baloons, and less in Aluminized Mylar (those “metal” looking baloons).
One can calculate the difference in mass between a tire filled with helium and one filled with air. An exercise I will leave for the student (hint: think Ideal Gas Law).
There will be a quiz on this next Thursday
Dr. Science
It would take over 3,000 balloons to make a 120 lb person float. One time my dad and I calculated it using mass numbers of helium vs nitrogen along with some other laws that I do not remember right now.
Surely this isn’t an ideal gas? The pressure is high enough that there may well be inter atomic interaction, and compresibility charts have to be used in order obtain a solution.
they floated a man with helium balloons, or at least a child, on myth busters.
Thanks for your answers. I did not think it would work but considered it an interesting conversational topic.
Another Helium Question, if i took a balloon (regular not matal coated or anything spesh) filled with helium, is it possible to submerge it? and if so is there anyway i could see the heilum leaving the balloon through bubbles? even if i left it there and recorded it. that would be quite a sight.
Dave;
You are correct, there are limits to the ideal behavior of gases. One model for correcting for this departure was developed by Van der Waals and is discussed here;
Here is the bottom line; it’s a very small correction for the pressures (2-3 atm) used in tires.
Or am i thinking to logically?
There is no such thing as thinking too logically. I would be possible to submerge the baloon given enough force, distributed properly. It’s hard to predict whether or not the He loss rate would produce visible bubbles on a reasonably short time scale (minutes). This is a case where one needs to do the experiment.
yey/yay!!
i am going to need a bunsen burner though, the best experiments always incorperate a bunsen burner.
Actually in all seriousness i might just try this. i think i have an old fishtank in the shed somewhere.
actually, another question Dr Science, make that two questions; If i place a regular balloon full of helium in an air tight container of some description, what would happen. would the helium leak out and mix with the air or would there be to much pressure for this to occur?
and also, where did you come from?