Helium Definition and 395 Threads

Sadly my physics knowledge has rusted since high school, and i'm struggling to find an answer to my question. would it be possible to compress helium in a standard 12g co2 cartridge? would it be possible to compress enough gas to fill a balloon? If compressing any helium in a cartridge is...

I am creating a helium particle accelerator and I have most of the measurement's down, such as the drift tube length, the pressure the system needs to be at ect. But I am stuck on what type of ion source I should use for the start of the whole thing. I have been leaning towards using a sputter...

I’m not at all sure I’m posting this in the right forum. If not, please forgive me. Also, I have no background in physics. That said, here goes: If 2bar of helium flowing through a 9.0mm inner diameter tube yields a flow rate of 15 liters per minute, what bar would one need to yield an...

IIRC, He_3 is usually separated from much less rare He_4 by cryogenic cooling of gas mix to 'liquid', at which point the mix divides to two phases, one with each isotope... IIRC, Hydrogen and Deuterium, as gas mix, may be progressively separated at near-ambient conditions by differential...

For this problem, How can energy be conserved if the bit highlighted in orange is true?Many thanks!

I have been self-studying the MIT 8.04 Introduction to Quantum Mechanics course. This question is not graded, so I have no reservation asking about it on the internet. Imagine an electron bound by tritium (Z=1). One of the two neutrons undergoes beta decay and becomes a proton, causing the...

Hello experts, First post here, and the reason I have found this forum is because I've spent the past few hours trying to figure something out. I'm in the field of data recovery, and we are starting to see helium filled drives. They are starting to be filled with HE due to factors like less...

How did you find PF?: By searching for a answer to my question and everyone only knows how helium effects the sound of their voice not mine.No one has a a answer to the question why doesn't helium have any effect on the sound of my voice? My question that no one has a answer to and ignores the...

The schrodinger equation for helium is (−ℏ^2/2me(∇21+∇22)+V(r1)+V(r2)+V(r12))ψ=Eψ V(r12)=1/(r12-r1) which makes the equation inseparable. Can other methods be used to solve it.

The Helium Network describes itself as a Community network of hotspots and claims to be a source of revenue for members. The literature (example here) only seems to talk in vague terms of providing connectivity via hotspots. I can see my neighbour's box on his chimney but I can't find any...

Are there any results on the structure of the helium atom eigenfunctions? By this I'm referring to the non-perturbative structure of the eigenfunctions, AKA what are the quantum numbers that one would use to label the eigenfunctions?

Hi, guys o/ Suppose a person sees a helium balloon moving horizontally at close to the speed of light. From this perspective, the observer will see the helium balloon contract in accordance with special relativity. If helium contracts to the point where it is denser than air, will it fall? how...

Hello All Diagrams of the Apollo Command Module show tanks of helium, What was this used for? best regards ... Stef

I read in 2 books that 4 atoms of Hydrogen fuse and give 1 atom of Helium and 2 electrons, and these 2 electrons convert to light. And that the mass of the Helium is less than the mass of the 4 atoms of Hydrogen, thus that the mass lost converted to light too. But I sum up the masses of...

I am having a trouble to understand why the helium's wave function (in which we are ignoring the electric interaction between the electrons, as well the motion and problems that arise in considering the nucleus in the wave function) can be written as the product of the wave function of both...

Any idea how much this would cost and how difficult? Should I forget about trying it myself and visit a university? Thanks

Here is the paper again: https://www.mdpi.com/2218-2004/6/2/22?type=check_update&version=2#related_content For a class project I need to calculate the energy levels of atoms using the Hartree Fock method as presented in this paper which essentially brute forces the calculation using finite...

The answer given to the above question is Final pressure$=\frac{(10.0mol\times 5.00bar) + (5.00 mol \times 20.0 bar)}{(10.0 mol +5.00 mol)}= 10.0 bar$ Is this answer correct? if yes, How and why? My question is while computing this answer, the volumes of each gas is not considered. Note:-...

Im doing a lab on an online software called beyond labs. On this software I am able to test gas laws by adding ideal and real gasses to a balloon in a pressure chamber. When I am conducting the test I have a consistent temperature of 298K and .300 moles across all the tests; the only variables...

Hello, I want to calculate the relative humidity in Helium. I only have the variables "dew point temperature", "gas temperature" and "gas pressure". So I tried with Magnus and Antoine equation. But I read that the Antoine equation is very unprecise. So do you know how to calculate the relative...

If you measure the location of an electron in helium, does it impact the expectation value for the location of the other? Also, can this experiment be conducted in practice? Thanks.

I was wondering about the following question. On the one hand, Helium 3 is spin 1/2. But, on the other hand, there are multiple combinations of internal spins that would lead to total spin being spin-up or spin-down. So what would happen if we insist that all helium 3 atoms are at lowest...

Red has the longest wavelength compared to the two other colours so the location of red will be at point C. x = 11.5 cm L = 30 cm d = 1870 nm Putting all into the formula, I get λ = 717 nm Where is my msitake? Thanks

An apparatus is constructed consisting of an electron beam, a Stern-Gerlach interferometer, and a target helium nucleus. The target helium nucleus is placed in front of the output beam of spin-up electrons. Two of the spin-up electrons are captured by the helium nucleus forming a stable helium...

one half mole of helium expanded adiabatically and quasi statically from an inital pressure of 5atm and temp of 500k to a final pressure of 1 atm. (a)Find the final temp and final vol. (b) work done by the gas (c) change in the internal energy of the gas.

I've heard of the universe being made up of 99% hydrogen. Is that just compared to all the matter in the universe or all of space(space wouldn't be empty then, so probably not). If there is hydrogen atoms floating around in space is there a known density (atoms per cubic meter for example)?

I've got a question asking me to find out the pressure of helium in outer space at 3K and density of 1 atom per cm3.I can't see why I can't just use PV = NkT, say V = 1m3, and N as molecules in 1 cubic metre = 1 x 106. However I know there's a fair bit more to it than this but I can't for the...

A helium ballon is used to lift a load of 110N. The weight of the balloon's skin is 50N, and the volume of the balloon when fully inflated is 32m3. The temperature of the air is 0oC and the atmosphere pressure is 1 atm. The balloon is inflated with sufficiet helium gas so that the new upward...

Anyway, here's my first post, and heres my question:About how many cubic feet of helium would be necessary to keep an average car, filled with water, afloat?Thanks!~~

Dear all, in my teaching of nuclear physics at high school level I noticed that I never really wondered about why alpha decay consists of helium nuclei. So I consulted a lot of lecture notes online, but couldn't find a satisfying answer. The texts I used in the past are "concepts of modern...

We consider a system composed of liquid helium in equilibrium with its vapor at very low temperature T, each phase being considered extensive. We neglect the mass of the gas compared to that of the liquid, as well as the heat capacities of the gas and the walls compared to that of the liquid...

Why do metalised film helium balloons only last about a week? Could I improve this result and make a balloon float for a year? (and don't cheat and say just make it bigger) how do I stop it leaking? Are there any better materials to make it from? (unlimited budget) As I understand aluminium...

Can you say whether I understood these things correctly? to get condition on wavefunction ##\Psi## for a system that consists of 2 electrons(without taking spin into account) and helium nuclei I can solve schrödinger equation: ##i*\frac{\partial \Psi}{\partial...

I thought the ratio was purely 4, because Helium's Z = 2 (atomic mass). Apparently this is not true, and now I'm stuck... I think there must be some other form of equation for the rydberg constant that is more general, but google and wikipedia are not helping that much. Any thoughts?

I am using a compressed gas tank to fill an otherwise empty container, The gas tank is around 50bar and the container will be filled to 6bar. If I am using a pressure transducer to determine when the container has been filled to 6bar, can I use the information I gain from it to derive the flow...

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Re page 14 of following reference: https://zenodo.org/record/1447321#.XSyx3z9LjIU If I understand correctly this page is showing a set of measurements for the fine structure of singly ionized Helium at +- 4686 Angstrom. Can we figure out from this which specific transitions are being measured...

Assuming you could get around the material and engineering problems with anything at high pressures what would happen if you kept pressurizing helium past a super solid state. If the pressures where high enough would you have a similar effect to metallic hydrogen with it behaving as a degenerate...

What does a helium balloon do on the ISS . most say, its a 0 g environment, but is it really the same as intercosmos travel "0g"? I saw a video of helium ballons on the vomit comet, where during the "0 g phase" the helium balloons went to the floor, while all other things floated. I would...

I don't think there is a thread on this? R Gusten et al, Nature, 2019, DOI: 10.1038/s41586-019-1090-x

Hey i have these ideas in which i use helium baloons. I wonder how high does it go and what is the gravity force and pressure at this point?

Most of the books I've seen they say that the first excited state of Helium (with two electrons, one in orbital 1s and other in 2s) can have the two electrons with parallel spin (orthohelium) or anti-parallel spin (parahelium). If ##\operatorname{X_{↑}}{\left (n \right )}## represent the state...

How to get to the expression for equilibrium recombination temperature for Helium?

Ugh ... I remember there was a reason ... but forgot what it was. So here's 3 bits of information gathered from dozens of sources, textbooks, official sites: Alpha particles are identical to Helium nuclei. Alpha particle mass = 4.001506 u helium-4 nuclei mass = 4.0026032 u OK, so ... why...

Can liquid helium is superfluidity state conduct heat infinitely fast? I thought I have seen this is a paper somewhere a long time ago, but now I am not sure about that.

Homework Statement Helium is kept in a pressure vessel at a pressure of 5.42 bar and the resulting density is 0.92 kg/m3. The gas constant R is 8.314 J/(mol*K). The volume of the vessel is 1589.194 m3. I need to find the temperature of helium in Celsius. Homework Equations...

Along the same lines as an earlier post about helium and materials that wouldn't allow it to permeate it, I wondered if a helium balloon with a fill tube would actually need to be sealed. What I mean is, imagine a balloon that has been filled with a 20'-30' very thin tube that is still attached...

Experts, I'm in need of a balloon to hold an RF antenna aloft, and that can have a light (LED) in it. For cost & safety, it appears Helium is the choice. But everything I'm reading says that He atoms are so tiny they pass (eventually) through traditional balloon materials quickly. There is a...

Helium has a higher 1st ionization energy (24.58eV) than N2 (15.6eV) and O2 (12.06eV). For an atmospheric room-temperature helium, why it is easier to get ionized than the daily life air under a same discharge setup? For example, for the Paschen curves, N2 locates at the left of He which means...

The Atom of Helium is doubly excited in 2p2 1D Can someone explain to me how these energy symbols work? I have a problem with what the 1D means specifically. I know 2p2 means two electrons in the 2p state. The 1 in 1D could be referring to electron being in a singleton, but I don't understand...