It is because the energy levels are proportional to 1/n2 1 / n 2, where n n is a non-negative integer. On the other hand, the extremely high speed of electrons (unlike that of planets) suggested that relativity be brought into the picture. 1 R( 1 n2f 1 n2i) (30.3.21) (30.3.21) 1 R ( 1 n f 2 1 n i 2) We see that Bohr’s theory of the hydrogen atom answers the question as to why this previously known formula describes the hydrogen spectrum. On the one hand, the positive analogy suggested that electrons (like planets) revolved around the center of mass of the atom (solar system). Furthermore, a related analogy between electrons and planets played a significant role in Bohr’s subsequent articulation of the model. The elaboration of the negative analogy led to the conclusion that the electron could move only in certain discrete orbits and its energy and angular momentum were accordingly restricted. We will argue that it was the negative, rather than the positive, analogy between intra-atomic electrons and the rings of Saturn that motivated Bohr to adopt and develop Rutherford’s atomic model. Bohrs model suggests that each atom has a set of unchangeable energy levels, and electrons in the electron cloud of that atom must be in one of those energy levels. In our paper we will stress the significance of negative analogies for the development of Bohr’s atom. 9.4: The Bohr Model - Atoms with Orbits is shared under a CK-12 license and was authored, remixed, and/or curated by Marisa Alviar-Agnew & Henry Agnew. The Bohr model, introduced by Danish physicist Niels Bohr in 1913, was a key step on the journey to understand atoms. Now, a hydrogen atom is usually in ‘Ground State’ at room temperature. This value agrees with the experimental value of ionization energy too.

This energy is the ‘Ionization Energy’ of the hydrogen atom.

However, she underappreciated the role of negative analogies in model-building. Hence, the minimum energy required to free an electron from the ground state of an atom is 13.6 eV. Modern scholarship on analogy takes its departure from the work of Mary Hesse, who pointed out the existence of negative analogies between two different physical systems, that is, those respects in which the two systems clearly differ.

The significant role of models and analogies in scientific practice has been widely recognized.

Bohr's model of an atom