
related topics 
{math, energy, light} 
{math, number, function} 
{theory, work, human} 
{acid, form, water} 
{style, bgcolor, rowspan} 

In atomic physics, the Bohr model, devised by Niels Bohr, depicts the atom as a small, positively charged nucleus surrounded by electrons that travel in circular orbits around the nucleusâ€”similar in structure to the solar system, but with electrostatic forces providing attraction, rather than gravity. This was an improvement on the earlier cubic model (1902), the plumpudding model (1904), the Saturnian model (1904), and the Rutherford model (1911). Since the Bohr model is a quantum physicsbased modification of the Rutherford model, many sources combine the two, referring to the Rutherfordâ€“Bohr model.
Introduced by Niels Bohr in 1913, the model's key success lay in explaining the Rydberg formula for the spectral emission lines of atomic hydrogen. While the Rydberg formula had been known experimentally, it did not gain a theoretical underpinning until the Bohr model was introduced. Not only did the Bohr model explain the reason for the structure of the Rydberg formula, it also provided a justification for its empirical results in terms of fundamental physical constants.
The Bohr model is a primitive model of the hydrogen atom. As a theory, it can be derived as a firstorder approximation of the hydrogen atom using the broader and much more accurate quantum mechanics, and thus may be considered to be an obsolete scientific theory. However, because of its simplicity, and its correct results for selected systems (see below for application), the Bohr model is still commonly taught to introduce students to quantum mechanics, before moving on to the more accurate but more complex valence shell atom. A related model was originally proposed by Arthur Erich Haas in 1910, but was rejected. The quantum theory of the period between Planck's discovery of the quantum (1900) and the advent of a fullblown quantum mechanics (1925) is often referred to as the old quantum theory.
Contents
Full article ▸


related documents 
Vega 
Cygnus X1 
Light 
Loop quantum gravity 
Luminiferous aether 
Cosmic inflation 
Surface tension 
Momentum 
Uncertainty principle 
Photon 
Andromeda Galaxy 
Astronomy 
Open cluster 
Orbit 
Stellar classification 
Holography 
Binary star 
Time travel 
Speed of light 
History of astronomy 
Physical cosmology 
Bernoulli's principle 
Spacetime 
Planet 
Electricity 
Lightning 
Dirac equation 
Extrasolar planet 
Centripetal force 
Vacuum 
