Re: OT: anyone worked with helium and blimps befor

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Harold: I found this on the net by doing a google search on "helium lifting power" Hope it helps:

Helium Lift Power

name Paul

status other

age 30s

Question - I would like to know the lifting power of Helium

eg: How much helium to lift 1kg

Any information would we great.

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Revised May 2008

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That depends on the density of air and the density of the helium. For

simplicity's sake, let's say the air and the helium are at the same

temperature and pressure. In that case, four grams of helium will occupy

about the same volume as 28.5 gm/mole of air. To lift an object, you need for

the mass of the object + the mass of the helium to be less than the mass of

the air it displaces. Since any object you want to lift will probably have

a much greater density than air or helium, let's neglect its volume for

simplicity's sake (in other words, we'll neglect the mass of the air

displaced by the object, because it will probably be only a small part of

the mass of the air displaced by the helium and the object together). Then

we can say that you need the mass of the object + helium to be less than

the mass of the air displaced by the helium.

M + Mh < Ma,

where M is the mass of the object, Mh is the mass of the helium, and Ma is

the mass of the air displaced. Our shortcut of neglecting the volume of

the object just says that

Ma = (28.5/4)Mh,

that is, a given mass of of helium will displace (28.5/4) times its mass of air.

Knowing that 4 grams of helium occupies that same volume as 28.5 grams of

air, we can see that four grams of helium will lift almost 25 grams:

M + Mh < Ma

M + Mh < (28.5/4)Mh

M < (28.5/4)Mh - Mh

M < Mh [(28.5/4) - 1]

M < Mh (7.125 - 1)

M < Mh (6.125)

M < 4g (6.125)

M < 24.5 g.

An easier way to look at this is to note that since four grams of helium displaces 28.5 grams of air, the "payload" for the helium is 28.5 g - 4 g = 24.5 g.

On a per gram basis, this means that one gram of helium will lift a payload (including the mass of the balloon) of (24.5 g payload)/(4 g helium) = 6.125 g payload /g helium. You can also see this in the above derivation if you just figure the mass of helium to be 1 g instead of 4 g.

So, to lift 1000 grams (1 kg), you need about 163 grams (~0.16 kg) of helium:

M < Mh (6.125)

M/(6.125) < Mh

Mh > (1000g)/ (6.125)

Mh > 163.3 g.

How much volume of helium is this? It depends on the temperature and

pressure. Neglecting the volume of the object to be lifted becomes a more

serious error as it becomes a larger fraction of the total volume. Under

normal conditions (ambient temperature and pressure), this is a small error.

Mike

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Subject Written By Posted
OT: anyone worked with helium and blimps before?Topic by: Homoped 06/04/08 03:27PM
Re: OT: anyone worked with helium and blimps beforRe: ~ DeeZy 06/04/08 03:30PM
Re: OT: anyone worked with helium and blimps beforRe: Cleats Onionpockets 06/04/08 03:34PM
Re: OT: anyone worked with helium and blimps beforRe: Homoped 06/04/08 03:47PM
Re: OT: anyone worked with helium and blimps beforRe: Mozes 06/04/08 04:15PM
Re: OT: anyone worked with helium and blimps beforRe: homoped 06/04/08 03:55PM
Re: OT: anyone worked with helium and blimps beforRe: Stoops 06/04/08 03:59PM
Re: OT: anyone worked with helium and blimps beforRe: ~ DeeZy 06/04/08 04:00PM
Re: OT: anyone worked with helium and blimps beforRe: Homoped 06/04/08 04:06PM
Re: OT: anyone worked with helium and blimps beforRe: ~ DeeZy 06/04/08 04:11PM
Re: OT: anyone worked with helium and blimps beforRe: Matt Scout The Scouting Dcon 06/04/08 04:37PM
Re: OT: anyone worked with helium and blimps beforRe: Silverfox Sullivan 06/04/08 05:36PM
Re: OT: anyone worked with helium and blimps beforRe: black_twingle 06/04/08 05:53PM
Re: OT: anyone worked with helium and blimps beforRe: russg 06/04/08 06:02PM
Re: OT: anyone worked with helium and blimps beforRe: ike 06/04/08 06:35PM
Re: OT: anyone worked with helium and blimps beforRe: ike 06/04/08 06:39PM
Re: OT: anyone worked with helium and blimps beforRe: Mopeder 06/04/08 06:49PM
Re: OT: anyone worked with helium and blimps beforRe: Noah 06/04/08 07:26PM
Re: OT: anyone worked with helium and blimps beforRe: Homoped 06/04/08 07:29PM
Re: OT: anyone worked with helium and blimps beforRe: Alex 06/04/08 07:52PM
SUCCESS!!Re: homoFUCKYEAHped 06/05/08 06:25PM
Re: SUCCESS!!Re: mopedrockdude 06/05/08 06:34PM
Re: SUCCESS!!Re: mopedrockdude 06/05/08 06:42PM
Here is the vid!Re: homoFUCKYEAHped 06/05/08 07:48PM
Re: Here is the vid!Re: Zeke 06/06/08 01:21PM
Re: Here is the vid!Re: Mozes 06/06/08 06:11PM
Re: Here is the vid!Re: homoped 06/06/08 07:02PM
Re: Here is the vid!Re: Gimmyjimmy . 06/06/08 07:17PM
Re: Here is the vid!Re: Bad Adam 06/06/08 09:13PM
Re: Here is the vid!Re: Gabe Bandit 06/06/08 11:27PM
Re: Here is the vid!Re: ike 06/07/08 11:22AM

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