how much weight could helium baloon lift?

[qwerty]

sorry if this is in wrong section but..best i could see

 

as topic title says.., how much weight could one normal sized helium balloon lift, the ones you get at the circus/show/party/whatever?

 

or to be more exact, how many would be needed to lift say 100g? thanks in advance.

[mezarashi]

I'd think google could probably help you here. A search for "helium balloon lift" would probably do the trick ^^. In principle however, the helium balloon works on the principle of bouyancy the same way certain things float in water. You can take the weight of the air displaced by the helium balloon as the bouyant force on it, causing it to "levitate". Of course, since we must take the weight measurements in air itself, you'll probably have to use the density of air vs density of helium instead.

[insane_alien]

the helium used to fill the balloons at circus etc. isn't pure helium theres some air mixed in as well so commercial "helium" has lesslifting capacity than laboratory helium

[YT2095]

ok, not very scientific I know, but I`ve just tested this, and 10 grams can be lifted easily by these ballons and with the helium I`m using, 11 grams is roughly neautral bouyancey, so 100 grams I`de estimate would need 9 of these ballons.

 

hope that helps a little

[swansont]

A mole of air at STP, (for the sake of argument say it's all Nitrogen) will displace ~22.4 L (assuming it's close to ideal gas behavior) and have a mass of 28g. A mole of He will have a mass of 4g. This mass will be somewhat larger as you increase the pressure above atmosphere to fill the balloon. So you can lift ~ 1g/L, including the mass of the balloon; larger balloons should be more efficient if you can maintain a constant wall thickness because the balloon mass will increase like the area, and the lift increases with volume.

 

Thus I predict that YT's balloons were roughly 10L in volume.

 

[pause to Google]

 

Here is more info along with some more precise numbers.

 

A 10L balloon is between 10 and 12 inches in diameter.

[YT2095]

WOW! exactly 10" dia on the card former (that`s suggested blowing up size), I always add a little more, the height is 14" suggested mine would have been a little bigger. I didn`t measure the balloon though, and I breathed all the helium that was in it, so I`ll go blow another up and measure it.

I didn`t use string either, I sellotaped the weight to the balloon.

Nice work Swansont!

 

edit: Yup, it was 10.5 inch dia and nearly 16" in length. rubber balloons too, not the metalised sort.

[insane_alien]

the metal foil baloons suck they burst too easily and don't have any give like the latex baloons

[mmalluck]

But the latex balloons leak helium much much faster than the mylar ballloons.

 

Choose the right balloon for your application:

A latex balloon for better lifting capabilities, but reduced flying time

or

A partially full mylar balloon for a long flight time but less lifting power

[YT2095]

actualy Mylar is just as good as latex, probably better, the only problem with it over latex is its refusal to expand in the same way.

 

gas volume per gas volume, I`de go the half filled Mylar route anyday

[DQW]

A mole of air at STP, (for the sake of argument say it's all Nitrogen) will displace ~22.4 L (assuming it's close to ideal gas behavior) and have a mass of 28g. A mole of He will have a mass of 4g. This mass will be somewhat larger as you increase the pressure above atmosphere to fill the balloon. So you can lift ~ 1g/L, including the mass of the balloon[/u'];

How did you get that ? Are the balloons that heavy (around 23 to 24 g each) ?

[swansont]

How did you get that ? Are the balloons that heavy (around 23 to 24 g each) ?

 

 

The mass differential was a little bigger than 22.4 g (24 g) and the volume was 22.4 L for the ideal gas. Divide the two. You get ~1g/L

[DQW]

Whoops ! Forgot to divide ! <looks around for rock to crawl behind>

[Locrian]

Great thread