Helium

[jordan]

Is there an easy way to calculate how weight a give quantity of helium can lift?

[Phi for All]

You can usually go by 1 cubic foot of helium to 1 ounce of payload, including the balloon.

 

 

You're not going to pull a Larry Walters, are you jordan?

[Thales]

That or calculate the difference in weight between the amount of air you displace vs weight of the amount of helium used to displace it. The resuling difference will yield the net amount of weight you can lift. Temperature can effect the measurement though, but other than that it is a simple bouyancy calculation.

[Primarygun]

Weight/Volume?

Is that we find out the density of the mixture?

Or use [(helium's density- air's density)*volume+Object's mass]/total volume=a?

If a is larger than air's density, it sinks.

It is just determine the lift or the sink of the mixture.

I just take a try here. Therefore, don't be too serious of it.I hope the solver would give us the correct answer.

[Phi for All]

Temperature can effect the measurement though, but other than that it is a simple bouyancy calculation.

I forgot about altitude as well. I'm at 5200+ feet above sea level. Would that affect it?

[Thales]

Yes but only because the air is less dense and colder. Essentially incorporating the method of the weight of air displaced vs the weight of helium used to displace will yield the amount of weight able to be buoyed. There is definately an altitude limit associated with the fact that the atmosphere becomes thinner at increasing height and there for weighs less. If the average weight per cubic cm of the atmosphere does not exceed the average weight per cubic cm of helium (at the same temperature) then buoyancy cannot be achieved, well at least not with helium.

 

*An interesting aside, helium was dicovered in/on the sun prior to it being identified on earth, thus the term helium, related to latin; helios.

[pulkit]

The problem is equivalent to that of a body floating in a fluid (Archimedes principle), its a question of bouyancy that helium experiences in air. Beyond a certain altitude, no rise is possible as density of helium will match density of air.

[jordan]

You're not going to pull a Larry Walters, are you jordan?

Maybe...

 

So if I said I have 1 pound sitting on my table then I tie 1 ft³ of helium to it, what would it weigh?

Phi, you say it would weigh about 15 oz?

[Phi for All]

Phi, you say it would weigh about 15 oz?

So this is a diet formula rather than a travel method!

 

It would work that way also. 1 cu ft of helium should make anything weigh 1 oz less if it is attached so as to lift it. So a 150# balloon vendor carrying 2399 16" balloons (approx 1 cu ft helium per balloon) would weigh 1 ounce.

[Primarygun]

Is the only buoyant force to be determined?

Moreover, can someone tell me whether my last post was correct.

[pulkit]

Is the only buoyant force to be determined?

 

Draw Free Body Diagram of sytem (Balloon + Object). Represent all forces (including bouyancy) and just apply F=ma along each axis.

[Primarygun]

Is the buoyant created by the density?

If it is, I will immediately learn the buoyant force.

I am very curous about the density of lifting and sinking.

[Primarygun]

I put my brain forward.LOL

And read a part of the buoyant force.

I think it could calculate the lift or sink action for fluids.

Is the lift or sink for a object in gas(air) simply being told by this force?

[pulkit]

I put my brain forward.LOL

And read a part of the buoyant force.

I think it could calculate the lift or sink action for fluids.

Is the lift or sink for a object in gas(air) simply being told by this force?

 

Its a major factor in determining the dynamics of a body in a fluid. And since air is a fluid, its a determining factor here too.

[Primarygun]

Thanks!