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2
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2answers
29 views

Why did James Chadwick use berryllium to discover neutrons?

In Rutherford's alpha particle scattering experiment he used gold foil because it's malleable and can be drawn into very thin sheet. Why did James Chadwick use Berryllium while discovering neutrons ...
1
vote
0answers
22 views

How does a Collider work? [closed]

How does a collider work, explained using various Physics theories (or if there is a main one) . How does the acceleration play a part in the individual sub-atomic kinetic levels. What happens when ...
2
votes
1answer
77 views

Photons Disappear and Reappear from Atoms?

Where does photons come from and disappear to? Can photons be destroyed and created? Without atoms would photons exist?
1
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0answers
34 views

Low kenitic Energy and High Kinetic Energy Atoms Attract

Will atoms of 2 difrent energy levels electron and/or Kinetic attract more than 2 Atoms at he same energy level? Do 2 high energy level atoms attract more than 2 low energy atoms?
1
vote
1answer
263 views

Proton scattering off electrons

I'm looking at a question which starts off as: A proton is travelling through a material and scattering the electrons in the material. Express the scattering angle in terms of the impact parameter, ...
3
votes
2answers
49 views

Beta decay of radiocarbon

I read some weird equation on wikipedia about the beta decay of radiocarbon: ${^{14}_{6}C} \rightarrow {^{14}_{7}N} + e^{-} + \overline{\nu_{e}}$ The problem with this equation that it does not ...
1
vote
1answer
27 views

Doesn't the subsequent change in effective nuclear charge and atomic radii disrupt the standing wave in which electron moves?

Electrons move in standing waves around the nucleus. However, as the Atomic No. along a period increases, the effective nuclear charge on the valence electrons increases and the atomic radii decrease. ...
1
vote
2answers
122 views

Red Photon Blue Photon

Why in space red light travels farther and is more observed in dying stars before a star becomes a black hole? while on Earth in water and air the blue light travels the farthest. For example: a ...
4
votes
4answers
129 views

Why don't we have more elements?

By looking at the number of subatomic particles there seem to exist, there should be thousands of element configuration combinations possible. But we have found just over hundred elements to exist. ...
19
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2answers
6k views

Are all electrons identical?

Why should two sub-atomic (or elementary particle) - say electrons need to have identical static properties - identical mass, identical charge? Why can't they differ between each other by a very ...
1
vote
2answers
56 views

How do you determine if the spin is up or down?

Fundamental particles such as quarks and leptons can have a spin either up or down. These spins are (obviously) opposite of each other. But what differentiates them? Let's say you examine a pair of ...
0
votes
1answer
44 views

Atoms Inside a Lightning Bolt

What happens to atoms trapped in lightning? Why do electrons not split an atom but can change them inside the bolt? Can atoms travel on a bolt?
0
votes
0answers
233 views

Source of electrons in Crooks tube experiment (Inside the Discharge tube)

In the experiment, gases are put at low pressure inside the discharge tube. Now the issue that arises is a very simple one. This is the animation for the experiment. Its pretty obvious that the ...
0
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0answers
24 views

Bonding Two Cationic Hydrogen Isotopes (protium) yields H2 or He?

If you have two hydrogen atoms. And they are the isotope form "Protium" (1 neutron removed) and they are also cationized +1 (1 electron removed) then you have (in a sense) a single proton (two of them ...
2
votes
2answers
793 views

Do electrons have a radius when they behave like a particle?

I know sometimes electrons behave like waves, but it sometimes can be seen as a particle. while it's a particle, does it have a radius? or, a volume? If it doesn't even have a volume, how can we still ...
0
votes
2answers
21 views

Probability of splitting nucleus

I'm sorry if this is a dumb question, but I was just wondering. Say we have a 20 x 20 cm sheet of sulphur, and we have a knife made of iron. If I take the knife, and repeatedly cut the sulphur for an ...
0
votes
1answer
109 views

Does the neutrino have charge? Obviously not!

I was recently reading "Particle Physics: A Very Short Introduction" by Oxford University Press, and in it (I haven't finished it yet though) he says, "The weak force changes one variety of ...
-4
votes
1answer
66 views

what make orbitals and can they be destroyed? [closed]

What is making an orbital to be an orbital? I mean how are the orbital formed. If big bang theory is true that there was nothing before the big bang then definitely these orbitals in the atom would ...
11
votes
4answers
2k views

Intrinsic structure of electron

The electron contains finite negative charge. The same charges repel each other. What makes electron stable and why does it not burst? Is it a law of nature that the electron charge is the smallest ...
-2
votes
2answers
974 views

Energy source of electrons?

I am aware that electrons are moving in an empty space so basically there is no friction to slow it down and its velocity stays the same. However where did the electron get its energy from in the ...
1
vote
1answer
53 views

How might we measure the size of a proton? (Without high energy collisions) [closed]

What methods could we use to measure the diameter of sub-atomic particles. Please think of something inventive, like an indirect technique. Or name some of the lesser known techniques that have been ...
1
vote
1answer
172 views

Do subatomic particles have finite size?

We know atoms are mostly "made" out of empty space, so the nucleus and all the subatomic particle are very small in compared to the magnitude of the atoms. We also know that atoms are incredibly ...
1
vote
2answers
111 views

Are there unobservable, undiscovered atoms?

Is it possible that there is a network of atomic activity that our current scientific instrumentation cannot detect? In other words, could it be possible that there are unobservable, undiscovered ...
-1
votes
1answer
580 views

Why does mass in the universe have no limit in large size, but has a limit in small size?

We found VY Canis Majoris, a star so big it can't even be seen in scaled illustratations with the sun itself. However, we stop at particle physics, or quantum mechanics, i.e. particles, subatomic, ...
5
votes
2answers
255 views

If mesons were stable could they form atoms?

if there were stable enough mesons similar to protons and neutrons could they capture electrons to form exotic elements. if not why is this not possible?
79
votes
5answers
19k views

What does it mean for two objects to “touch”?

If you've ever been annoyingly poked by a geek, you might be familiar with the semi-nerdy obnoxious response of "I'm not actually touching you! The electrons in the atoms of my skin are just ...
1
vote
1answer
86 views

Is there a repulsive force between neutrons at all distances or just real close?

With particles of the same charge there is a repulsive force at all distances and physicists talk about neutrons repelling each other. Does this repulsion occur at all distances like with charges ...
2
votes
3answers
195 views

Why do neutrons decay after 6 minutes?

If I understand correctly, Beta decay only occurs when an atom (or in this case subatomic particle) is unstable. Are neutrons consider unstable? If so why? And if they are not unstable is there is ...
-1
votes
1answer
84 views
0
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3answers
199 views

What evidence is there for quantum leaps?

I find this very strange that an electron can 'teleport' from one energy level to another. So what evidence suggests this?
2
votes
4answers
436 views

Has a photon or electron ever been observed in a state of superposition?

Has subatomic particles ever been seen in a state of superposition or do we just detect information like qubits about the state of the particle? So is actual matter in superposition or is it just ...
1
vote
1answer
94 views

Where does the mass of a nucleon originate in an atom?

The mass of the three quarks in the nucleons make up only about one to two percent of the mass of the nucleons. What makes up the other 98 percent?
0
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0answers
236 views

Is there a limit to what we zoom into if it is in fact infinite

I read that recently we were able to view the first atom (hydrogen) under a microscope. This got me thinking about the idea of measurements and zoom lenses. Say hypothetically we were able to build a ...
1
vote
3answers
595 views

New subatomic particles

In reference to the findings talked about here http://online.wsj.com/articles/two-new-subatomic-particles-found-using-large-hadron-collider-scientists-say-1416409980 and other similar articles ...
0
votes
0answers
47 views

Why does not electron cloud collapse over Nucleus? [duplicate]

Gravitational Force & Electrostatic Force should have attracted electron cloud & collapse it over positively charged nucleus.But it doesnot happen One rationale I find behind the phenomenon ...
7
votes
1answer
1k views

Anti-Matter for Neutrons

The anti-particle corresponding to a proton or an electron is a particle with an equal mass, but an opposite charge. So what is the anti-particle corresponding to a neutron (which does not possess a ...
7
votes
2answers
762 views

Miniature Neutron Stars?

Is the nucleus of a carbon atom, for example, as dense as a neutron star? I read that neuton stars also contain protons. Thinking more broadly, are we surrounded by quadrillion of quadrillions of ...
-2
votes
1answer
255 views

Physical -> Chemical -> Nuclear -> (what comes next)

If a splitting atoms / fusing isotopes (fission bomb, fusion bomb) yields more energy than chemical changes (TNT, et al) yields more energy than physical change (hydrogen bonds forming during water ...
5
votes
2answers
972 views

How many subatomic particles can absorb/emit photons?

Is the electron the only subatomic particle that can absorb and emit a photon?
0
votes
2answers
287 views

What does temperature look like at the subatomic level?

I am trying to get a better understanding of the definition of temperature at the subatomic level. I have a background in molecular biology with some college physics, but no deep quantum mechanics ...
1
vote
1answer
232 views

Atomic physics question - exciting of electrons during bonding

As I have learnt, when bonding takes place in an atom, such as carbon, the electron in its $s$-subshell gets excited and jumps to the open spot in the $p$-subshell. This is why carbon is able to form ...
1
vote
1answer
221 views

Are subatomic partices n-dimensional hyperspheres or another n-dimensional shape?

This guy derives the formula for the volume of an n-dimensional hypersphere, which can also be found here on the Wikipedia page, and he shows that it is equal to this equation: $V_n = ...
2
votes
1answer
221 views

Why is water blue (on a quantum level)

OK, lets formulate it differently and say water works as a blue passing / red restricting filter. It is actually observable. Just do a dive in a swimming pool with white light (maybe even at night) ...
1
vote
1answer
81 views

Nuclear fission mechanism: neutron capture

Consider this nuclear fission reaction: $\mathrm{^{235}U+{}^1n\to{}^{236}U \text{ (excited)}\to{} ^{92}Kr+{}^{141}Ba+3{}^1n}$ I have not understand why a thermal neutron ($^1$n with $E\simeq 0.025$ ...
0
votes
1answer
81 views

quarks annihilation process

I am appreciating particle physics and I read about mesons. In quark's model, mesons are pairs of quark-antiquark. Now I think that in general matter-antimatter annihilate and so I don't understand ...
1
vote
0answers
45 views

Subnuclear physics vs wave function

This question is more a philosophical question than a physics one. When we appreciate particle physics we study that in order to explain some experimental results we have to introduce a new particle ...
4
votes
2answers
425 views

Are nodes and orbitals in atoms simply probability distribution clouds or are they of any physical relevance?

I fail to understand what the electron clouds actually signify. Such as the $p$ orbitals, which have a dumbbell like shape. Now I am aware that they aren't actual trajectories of electrons, but what ...
1
vote
1answer
66 views

How we can manipulate the momentum of a particle?

Is there any way to affect a particle's momentum value?
0
votes
0answers
36 views

Definition of momentum-entangled particles

When we can say that two particle are momentum entangled ? I just read an article where it's said that two momentum entangled particles share the same momentum value in opposite directions no matter ...
5
votes
1answer
125 views

What does energy represent in $E= mc^2$?

Due to energy-mass equivalence, any object with mass can be said to have a corresponding amount of energy. So in a 5kg object there are 450,000,000,000 joules. A joule as i understand it is the ...