# Helium question?

1. Oct 1, 2008

### Photon713

If I filled a 4-5 foot piece of surgical hose with helium, would it stand vertically? How long would it remain assuming both ends were sealed? Would some other flexible material work better? A balloon on a string would not work for my purpose. Thank You

2. Oct 2, 2008

### Redbelly98

Staff Emeritus
I doubt it, since surgical hose has a rather thick wall. The weight of the hose would probably offset the buoyancy of the helium.

3. Oct 2, 2008

### Munfred

Well, you can just do the maths and discover by yourself. You just need to know how much the hose weights, and its volume(total and internal, although just internal will do). Then just calculate how much the hose filled with helium weights, and how much the same volume or air weights. If the hose weights less, it'll float, if it weights just slightly more it's very likely stand up, if it weights considerably more it'll just remain on the ground.

4. Oct 3, 2008

### Staff: Mentor

Where is the border between slightly and considerably?

5. Oct 3, 2008

### Munfred

Well now that's quite a good question, but 'slightly' would be like when you have your helium balloon with the string on it and it floats with some string on the ground. in this case the balloon + string weights is just slightly more than the same volume in air. If it simply cant get off the ground then it weights considerably more.

6. Oct 4, 2008

### Redbelly98

Staff Emeritus
With the balloon, the string acts as a regulator. The balloon rises until it's weight plus the amount of string not resting on the ground equals the weight of air being displaced.

If the balloon rises higher, more string weight is added and it sinks back. If it sinks too low, it has less weight from the string and will rise back up.

The tubing does not have such a regulator, so that is a problem. I.e., it will either float to the ceiling, or fall over. You can't get it exactly right.