Vacuum discussions!

Now some of you might find this a really silly subject, however i find it quite facinating to debate these kind of things and thus place it in the General area, if it gets out of hand i wont mind it being moved to the span can. I would prefer if we can keep this above the level of spam.

This is pretty much theoretical but here goes:
Imagine a regular inflated party balloon, ignore the material it is made off.
Now if we exchange the air inside with a vacuum while maintaining the shape. (filling it with a vacuum)
Would that balloon rise, because it weighs less than the surrounding air.
Or do nothing since there is absolutly no force pushing it upward.

Then as a side track, if it does rise, think it would have much lifting power?
Revolutionize the aviation?

I myself think it would do nothing.
So what you're saying is if you had a balloon made of a very light substance, and containing a complete vacuum (while still being strong enough to not collapse under the internal pressure), would it float?

According to physics, yes it would float. However, one would have to have a very light substance capable of withstanding a very large amount of pressure. It would be a battle between weight and vacuum volume capacity.

I would love to see something like that in practice, but I don't think we have the materials capable of containing a perfect vacuum AND having a very low weight.

Edit: And though it may seem a bit silly, it's good ponder fodder. XD

Edit2: An example of what magnitude of force you'd have to contend with:
Ah yea thats when they fill it with steam and then pour cold water on the outside right?

I saw something similar aswell.

The potential power of a vacuum is awesome but im really interested in its bouyance aswell.

Also this thread wont die this easy.. i want other peoples thoughts/opinions aswell Dx

Just because we know what physics "should" make it do doesnt mean it actually will do that.. Glass is actually liquid and Blood can turn solid when impacted..
Vacuum goes where?

D :

Well, when you're able to create solid matter out of air particles, gimme a call.


Sorry, can't make long-distance calls. :I

I don't think there is anything you could call a perfect vacuum, though, what with the subatomic particles flying through space and all. If you want the buoyancy of a vacuum, you can just stick Archimedes' principle in it. Weight of substance displaced = Buoyant force. Same thing used to calculate buoyancy of helium.

Only reason anything containing a vacuum doesn't float is because the material's too heavy. That's all. It would be a far stretch to make such a strong material that can withstand all that atmospheric pressure.
You could like, create the vacuum somewhere out in the thermosphere where the air pressure is lower so you can use a material that can withstand the pressure while still being light enough... or something.