SpudFiles

As I was sitting in my tree stand early saturday morning, awaiting a deer to walk by I had thought of something kool...

Ok what I was thinking was that if you pressurize a container or somthing with helium would it make that object more bouyant in the air. because then you could shoot it and it would go farther. maybe even get it to defy gravity. Its just an idea but I was thinking of makin a copper capsule or somthing to try it out here is a pic. or you can just correct me so i dont waste my time...
http://i139.photobucket.com/albums/q317 ... psule-.jpg

King_TaTer

I dont kno why scientifically. but the helium doesnt really do anything. you can try it but the mythbusters filled footballs with helium and tested then against normal footballs and there was basically no difference

On behalf of PCGUY and PIMPMAN:

WHY IN THE CRAP ARE YOU POSTING IN HYBRID CANNON SHOWCASE!!!! YOU'RE NOT SHOWCASING A GUN AND THERE IS NOTHING TO DO WITH HYBRIDS HERE!!!!

Phew, now that that's out of me......Of course helium will make an object more bouyant in air. Helium is lighter than air so it floats, hello!

As to the mythbusters thing, there is a certain mass where an object can receive the most momentum from an object. In the case of footballs, the small extra bit of mass from the air versus the helium allowed a greater amount of force to be transfered. That's why it went farther.

sorry I posted in the wrong section lol I always do that for some odd reason. but what I really wanted to know was that if I made the capsule would I be able to fill it with enough helium that it would counter earths gravity and it would float. I know it probly wont work but oh well. just wonderin what you thought.

oh and sry the pic is so small it should enlarge to full screen but I dont know why

pressuriseing a container with helium will make it heavier than haveing the container full of helium at atmospheric pressure, sorry for spell mistakes this is all odne with a pinky.

-ps- tell me if i'm wrong about that.

Yeah if you pressurise it you will make it heavier. A copper pipe with 2 endcaps filled with helium should float. I'm sure you can find a chart somewhere online that shows how light something needs to be to float when filled with helium. As long as the copper pipe is light enough, it should work, and would look really cool.

Myhtbusters did a show on this with a football. There was no difference. I think by the time you got a projectile light enough for helium to show any negligable lift, you wouldn't have enough mass to oer come aerodynamic drag.

E

It might not go far, but how cool would it be to fire your potato gun, and have the ammo float away?

Um unless you have some ultra thin copper its not going to float, ya filling a container with helium will make it lighter but unless your container is light to begin with it will not float.

If you want to see how much lift it would get, I think 1000cubic feet will lift somewhere around 68 pounds, now you do the math to figure out how much lift would be gained and subtract it from the over all weight.

And making something lighter does not mean it will go further, there is always that "specific" weight that will let something travel the furthest depending on all outside variables, and making it lighter will not necessarily help.

Any way that's just my two cents.



Cannon Freak.

y not make it out of plastic or shoot a bollon with some water and helium in it im not sure if it would work

Where do you people come up with this stuff? Everybody's trying to increase the kinetic energy of their projectiles and you're filling them with helium?!

Well you'd have a dam low mass projectile....

It would accelerate like hell and lose energy like hell.

Probably drop dead 20m out of a 300psi cannon a bit like like firing a bunch of feathers....

thanks for adding your comments people I appreciate it. im going to do some more research on it... unfortunatly lol

If you were going to have a copper canister filled with heliem, it would be a better idea to remove all the air altogether and have a near- perfect vaccuum. No helium is even lighter than helium. Regardless, you could make the projectile that much lighter by leaveing air in it and fileing off a bit off the copper. It doesn't make a lot of lift, the only reason helium balloons float is that they are large but very light, making their overall density less than that of air. eg an empty balloon is denser than air by 10 units. a balloon filled with air is denser than air by 2 units. helium is less dense than air by 2.5 units. Therefore a helium balloon is less dense by 0.5 units, giving you 0.5 units of lift.

Those numbers are out of proportion, not to scale and were thought up on the spot. I'm just useing it as a way to explain that helium only generates lots of lift if the container is exceptionally light, and very large for its weight. Weight doesn't allow things to float, its all about density.

Its why a lump of steel dosen't float in water, but a hollow sphere with very thin walls made using the same amount of steel will.