Bohr atom model is still the textbook content of today's high school physics.  We all know that the Bohr model is only suitable for single electron hydrogen atom, not suitable for other atoms. For example it's not suitable for Helium atom with two electrons.  The Bohr model is obviously wrong. The atomic system based on this model has no mechanical stability, atoms can not exist this way. Hydrogen atom is a coincidental exception, because it has only one electron.  According to Coulomb's law, the electrical force between proton and electron provides centripetal force, which enables the electron to run in orbit. This is a model that physicists draw from the analogy of the solar system's planetary models. One electron Hydrogen atom is OK based on this scenario.  For helium atom with two electrons, this model can not provide mechanical stability, that is, two electrons can not exist stably around the nucleus.  The reason is simple: because there is also a great force between the two electrons. The magnitude of the repelling force is in the same level with the centripetal force, this must make the helium atom unstable.  Our solar system is stable because these planets are far enough apart, compared with sun's attraction,  the attractive force between planets are almost ignored. When multiple electrons move around the nuclear, the repulsive forces  between them are too strong and cannot be ignored, which will definitely destabilize the atom. Atoms are not the same as solar system.  For large atoms, it is easier to understand that the strong interaction between electrons makes atoms mechanically unstable. Outside the nucleus, a group of electrons with huge repulsive force are circling. How can we make the atom exist stably without disintegration?  Another error is that the Bohr model can't make up molecules (for example, two hydrogen atoms make up hydrogen molecule). No electron can circle two nuclei at close range due to mechanical stability problem. This is similar to the reasons why binary systems cannot have close common planets.   All the assumptions based on the Bohr model that electrons rotate around two or more nuclei to form chemical bonds are impossible. Electron is not a man driven space ship that can go anywhere the driver want.  Bohr (not only him, but many physicists at that time) was misled by the planetary model and came up with an incorrect model that only applies to hydrogen atom.  The atom model  suitable only for a single electron atom must not be the correct atomic structure.    In terms of atom stability, Bohr's circling model is correct only for hydrogen.  Considering other ways, it's not right, it is not suitable for hydrogen atom either.  The solar system will not disintegrate and reorganize. Once formed, it will remain unchanged until sun is too hot or to burn out.  Atoms are disintegrated and recombined at any time. The ionization of hydrogen atoms does so. Ionization means that atom break up into electron and proton, whereas proton and electron close together can merge into hydrogen atom.  Bohr's circling model can not complete this dismantle and rebuild process. The recombined electrons will crash onto the proton due to Coulomb force.
The  is essentially that the nucleus is a ball and the electrons are balls orbiting the nucleus in a rigid orbit.    This  chemists to find a model of chemical bonding where the electrons in the outer orbits could be exchanged. And it works pretty well as seen in the Lewis structures:    However,  were found to be less rigid and instead be fuzzy fields which, instead of being discrete/rigid orbits, look more like:     However, in chemistry education like organic chemistry you still learn about chemical reactions using essentially diagrams that are modified lewis structures that take into account information about electron orbitals:    What I'm wondering is, if the Bohr model is used essentially throughout college education in the form of these diagrams, it seems like it must be a pretty accurate model, even though it turns out atoms are more fuzzy structures than discrete billiard balls. So I'm wondering what the inaccuracies are, and if there is a better way to understand them than the Bohr model. If you build a computer simulation of atoms with the Bohr model, I'm wondering if it would be "accurate" in the sense of modeling atomic phenomena, or is it not a good model to perform simulations on. If not, I'm wondering what an alternative model is that is better for simulation. Essentially, how good the Bohr model is as a diagram, as a tool for learning, and as a tool for simulation.
Integral $\int\frac{2x^2}{2x\cos(2x)+(x^2-1)\sin(2x)} \mathrm d x$ Integrate  $\displaystyle\int\dfrac{2x^2}{2x\cos(2x)+(x^2-1)\sin(2x)} \mathrm d x$   I tried dividing by $\cos^2(x)$ and then substituting $\tan(x)=t$. 2 different bibliographies I'm writing my thesis and I would like to make 2 "bibliography" references: The first one would be for the publications I'm in and the second one for external references. I've made one *.bib file right now and it's working but I have no idea how I should work with 2 *.bib files.  Any suggestion will be appreciated. How to add a custom icon or symbol to a flag link? I'm working on a 'sample request' implementation for a commerce site using , , sessions and a little custom code.  I'd like to add an icon or a symbol to let people know that an item they are viewing has been flagged.  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Example: "Replacing the hard drive of this computer would be [idiom]. It's going to fail completely soon enough." I have an enum construct like this:  public enum EnumDisplayStatus {     None    = 1,     Visible = 2,     Hidden  = 3,     MarkedForDeletion = 4 }   In my database, the enumerations are referenced by value. My question is, how can I turn the number representation of the enum back to the string name.   For example, given 2 the result should be Visible. Let $F$ be a field. $(x-c)|(p(x)-p(c))$.   So if $x-c|p(x)=q(x)-\frac{r}{x-c}$ so for $x-c|p(x)-p(c)=s(x-c)-\frac{r}{x-c}$. Is that correct? Or is there a different way to go about proving this? I have proved that $x-c|p(x)$ has a remainder of $p(c)$ so It wuld make sense that $p(x)-p(c)$ would be $x-c$. Cannot log into Area 51 with OpenID Methods of speeding up a huge DELETE FROM  with no clauses Using SQL Server 2005.  I am performing a huge DELETE FROM  with no where clauses.  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Cannot get specific WMS to display in Leaflet or OpenLayers 3 What is the rationale for all comparisons returning false for IEEE754 NaN values?