A nucleus made of protons and neutrons surrounded by a cloud of electrons equal in number to the protons.

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2
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3answers
42 views

Demonstration that vibrating basic particles constitute non-vibrating individuals

I am a dilettante in physics; I ask for pardon for my confusion-causing (if any) terminology usage, and also for my imprecise choice of question tags. I know that basic particles of any individual ...
3
votes
1answer
36 views

Measuring Atomic Radius of a Noble Gas

How exactly can you measure the atomic radius of a noble gas such as Neon or Helium accurately? Would liquefaction help? I also heard that the aforementioned gases are the only common elements which ...
1
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0answers
49 views

Formation of atoms [closed]

If a Proton goes toward an Electron with a trajectory that forms a circular motion, these particles will form an atom ?
8
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3answers
801 views

How is it possible for objects to travel faster than the speed of sound when particles interact at the speed of sound

First of all, I am sorry if this is a stupid question but: I've heard that atoms interact with each other at the speed of sound (when you for instance push a chair, the atoms collide with each other ...
0
votes
1answer
84 views

What is a real world application of Madam Curie's life work?

As in the title. I know she was working with radioactive atoms and she made huge progress in the field of physics. But where would you find the application of her discoveries in our world? Is it just ...
6
votes
2answers
63 views

Why do $\beta$ particles not get attracted to the nucleus?

I currently have a very limited knowledge of how radiation works etc, but while sat in class the other day, one question occurred to me that even my teacher could not answer. We have been learning ...
1
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0answers
34 views

Space between particles [duplicate]

I am a high school student, and I am just wondering what is the space between each particle, like what is the gap around each atom? I have found no text book cover this topic. Is it a vacuum?
5
votes
3answers
132 views

What makes materials hard and strong?

This is something I have wondered for a long time. Why are some materials like steel, diamond, and even light materials like graphene stronger than others? Is it due to the strength of the ...
3
votes
2answers
246 views

Atomic nucleus consisting of only neutrons?

Is it true that the nucleus of all atoms (including radioactive isotopes) contain at least one proton? Is there an atomic nucleus consisting entirely of neutrons? (Let's exclude neutron stars for the ...
0
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1answer
38 views

Can an object be deconstructed on an atomic Level?

Can a machine deconstruct objects on an atomic level. But is that possible? Not the machine per say but the simple (not that simple) act of what it does. Ex.Taking a broken computer and separating the ...
3
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3answers
44 views

Real silicon atom structure?

Text books say that a pure silicon atom has four electrons in its outermost orbit. How do the scientists know it has four electrons?
-1
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1answer
27 views

Atoms and their bonds in an explosion

I was watching a video and when the car did blow up I asked to me... what happens with the atoms and their bonds when an object blows up of this way? what is the behavior of the atoms and their bonds ...
1
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2answers
26 views

Stopping an isolated metal ion

If we obtain something like a single isolated hydrogen atom I.e. $H^+$ is it possible by keeping it in a system of charged rings to contain and stop it at the centre of the system? Any positively ...
3
votes
4answers
109 views

Is there any significance of atomic orbitals?

We have been taught that the atomic orbitals we read about are probability density region of finding electrons of particular energies which are designated by the various quantum numbers. Since, there ...
0
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0answers
44 views

What are the longitudinal and transverse relaxation times in three level atom

Can anyone explain to me what is the longitudinal and transverse relaxation times in three level atom What is the physical meaning of them ? And how I can add the terms of relaxation time to the Bloch ...
1
vote
1answer
29 views

Resonating frequencies of atoms

I have a mathematics and computer science background with very little physics. I have read that the resonating frequency of an atom of some element is always exactly the same as the resonating ...
1
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2answers
47 views

Does the doppler shift have any effect on the energy that the atom absorbs?

Does an atom moving towards the light that is falling on it, absorb more energy than when it is stationary? The atom should a see blue shift due to Doppler effect so the atom will see a light of ...
6
votes
2answers
214 views

Why do electrons in an atom 'fall' back to the ground state?

Why, after absorbing a photon does an atom's electron 'fall' back to its ground state (what causes it to immediately lose its absorbed energy)?
0
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2answers
63 views

Mathematical description of electron configuration

Does there exist a mathematical model for determining the electron configuration of an atom? I mean the theory which would generalize the notion behind the informal elements of the Aufbau principle.
-3
votes
1answer
117 views

Have we ever seen an atom? If not, how do we know they exists? [duplicate]

Question is what exactly title says that have we ever seen an atom through any means (microscopes/equipments.etc)? If not, how do we know they exists?
0
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0answers
53 views

Which particles can go right through the atom?

Can elementary particles (like the electron, photon, or neutrino ) go through an atom (not the nucleus)?
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5answers
1k views

Can we squeeze atoms?

Lets consider few water molecules (or monoatomic noble gas or $H^+$ ions or electron gas) to be present inside a vessel, now if we enclose the vessel with certain hard material which could act as ...
1
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3answers
94 views

Do atoms of a surface excite to reflect the light?

How do surfaces reflect certain colours and absorb the others?
-3
votes
1answer
48 views

Angular momentum Bohr's model

I have been trying to derive speed, radius etc. in hydrogen atom using Bohr's postulates and not neglecting the coulombic attraction on proton. I know that they will be revolving around their centre ...
1
vote
1answer
97 views

How much smaller will be human body, when we hypothetically get of every space between particles [closed]

I had an interesting dream, where advanced civilization compress their body with technology, that turn off space betweens atoms/particles. They travel in small spaceship with billions citizens very ...
0
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3answers
38 views

In what form does proton give energy to electron?

According to Bohr, electron revolves around the nucleus because of force of attraction between electron and proton. This force of attraction gives energy to the electron. So my question is this that- ...
2
votes
1answer
48 views

Atomic transitions and density: clarification

A laser passes though a cell containing vapor of an alkaline element which causes atomic transitions. I was told that the formula for the atomic density in a Rubidium cell, for example, is given by: ...
1
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0answers
25 views

An EM problem of polarized sphere

Today, I'm doing an EM problem and my question is exactly the same as this site shows: http://www.physicsforums.com/showthread.php?t=133501 To reiterate my confusion, why we can't use that integral ...
0
votes
3answers
92 views

question on dipole moment of water molecule

I read a line today and don't get it: "Molecules with mirror symmetry like oxygen, nitrogen, carbon dioxide, and carbon tetrachloride have no permanent dipole moments." ...
0
votes
0answers
24 views

Rutherfords alpha scattering conclutions? [duplicate]

Please can some one give me rutherfords observations and his conclutions from each onbservation, I have looked in text books but they only give them sepratly with no direct link betweeen which ...
1
vote
1answer
85 views

Hydrogen ionization energy [closed]

Proton and electron have a distance equal to the Bohr radius apart in the hydrogen atom. Knowing this, what's the ionization energy of the atom? So we know $U = -kq^2/a_B$, but this is potential ...
2
votes
1answer
71 views

The position of center of mass of electron cloud in an atom

I read Griffiths EM today and it says something very interesting but a little bothering to me. It states for an atom, the position of center of mass of an electron cloud lies in the center of the ...
2
votes
1answer
120 views

Smallest possible object made of atoms that is spherical to a given degree [closed]

I recently saw a video, World's Roundest Object, which discussed a sphere made of silicon-28. The researcher in the video stated, if the object was scaled to the size of the Earth, the highest and ...
0
votes
1answer
125 views

Expectation value of energy from the position state of hydrogen atom [closed]

I was given with the position state of hydrogen atom: $$ R_{21} =\left(\sqrt{\frac{1}{3}}Y^0_1 + \sqrt{\frac{2}{3}}Y^1_1\right) $$ I am getting confused about getting the expectation value of ...
0
votes
1answer
94 views

Why electrons get excited? [closed]

Why and how are electrons get excited and what happen inside an atom when electrons get excited?
1
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2answers
68 views

Quarks are now considered to be fundamentals, but so were atoms some time ago. So the way we see is only limited by our technological advances? [duplicate]

After watching this FuseSchool - Global Education episode, I cannot stop thinking how can something not have a substructure, how it cannot be split? http://www.youtube.com/watch?v=nlv06lSAC7c
-1
votes
1answer
71 views

How do magnetic objects exhibit attraction/repulsion across empty space?

Magnets will attract or repel over a distance before physically touching each other. What makes this effect possible? My best guess is that the forces generated by the angular momentum of the ...
3
votes
2answers
96 views

Electron speed in Atoms

Is the speed of electrons in Atoms consistent in all Atoms or clusters/groups/individual elements, and if it is consistent in any atom, is that speed constant?
-1
votes
2answers
85 views

Are particles solid?

My intuitive understanding is that although atoms are mostly empty space, the nucleus is solid. Thus a neutron or a neutrino can collide with it and do things like deflect or cause a nuclear ...
1
vote
0answers
20 views

How does beta+ decay actually occur? [duplicate]

I'm having difficulty in understanding beta plus decay. How can a proton which has slightly less mass than neutron transform into a neutron, positron and neutrino? Form where does the extra mass for ...
3
votes
1answer
143 views

Do atomic nuclei have fixed orientation and position with respect to the electron cloud?

Does the nucleus of an atom of any element (besides protium) maintain a particular orientation in relation to its electron cloud? Does it bounce around within its cloud? Can it be ejected from its ...
2
votes
0answers
37 views

Cathode Ray Tube

I am considering the cathode ray tube of the set up, when the cathode rays were discovered Voltage = Very High Gas = any Atmospheric Pressure = We change (In the following example i am just changing ...
1
vote
2answers
93 views

Hydrogen atom: potential well and orbit radii

I happened to open up an old solid-state electronics book by Sah, and in it he says: "it is evident that the electron orbit radius is half the well radius at the energy level En" The orbit radius is ...
1
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2answers
55 views

Molecules and electrons energy types

What are the types of energy that an atom or a molecule could have? For example they have kinetic energy, could they also have other types?
2
votes
2answers
62 views

How do you know which atoms are in a specific piece of matter?

If you have a piece of matter in front of you, how can you know of which atoms it consists? And starting from nothing, how can I discover all the elements (or just a lot of them) of the periodic ...
31
votes
4answers
4k views

Are atoms unique?

Do atoms have any uniquely identifying characteristic besides their history? For example, if we had detailed information about a specific carbon atom from one of Planck's fingerprints, and could ...
1
vote
0answers
126 views

Show that the circumference of the Bohr orbit of hydrogen is an integral multiple of the wavelength of the electron in it [closed]

We have an electron revolving in a the $n$th Bohr orbit of an atom of hydrogen. The problem is to prove that the circumference of the orbit is an integral multiple of wavelength of this electron ...
2
votes
0answers
87 views

What are the assumptions behind “term symbols”?

In multi-electron atoms, the electronic state of the optically active "subshell" is often expressed in "term symbols" notation. I.e. $^{2S+1}L_J$. This presumes that the system of electrons has ...
0
votes
2answers
83 views

What happens to the atoms and their constituents when we break something ?

My query is: how does an atom stable itself. When we break something, what actually happens in the chemical bonding of its atoms, does it rupture or remain intact?
0
votes
1answer
166 views

Why is the charge on protons == to charge on electrons? [duplicate]

I am not a expert on physics, just another high schooler, so sorry if the question is obvious. This is something I've been wondering about for a while. Why is the charge on a proton equal but ...