Planck s quantum theory

The expressions in (3.72) and (3.73) are valid only for monatomic ideal gases such as He or Ar, and must be replaced by somewhat different expressions for diatomic or polyatomic molecules (Sidebar 3.8). However, the classical expressions for polyatomic heat capacity exhibit serious errors (except at high temperatures) due to the important effects of quantum mechanics. (The failure of classical mechanics to describe the heat capacities of polyatomic species motivated Einstein s pioneering application of Planck s quantum theory to molecular vibrational phenomena.) For present purposes, we may envision taking more accurate heat capacity data from experiment [e.g., in equations such as (3.84a)] if polyatomic species are to be considered. The term perfect gas is sometimes employed to distinguish the monatomic case [for which (3.72), (3.73) are satisfactory] from more general polyatomic ideal gases with Cv> nR. 

In 1913 Niels Bohr proposed his atomic theory with the help of the line spectrum of hydrogen atoms and Planck s quantum theory. His postulates can be summarized as follows ... 

Further work on similar types of cells has been carried out, in which not only is use made of the Nernst Theorem but likewise of the Einstein theory of atomic heat of solids (as modified by Nernst and Lmdemann) This will be taken up after we have discussed Planck s Quantum Theory of radiation and Einstein s application of it to the heat capacity of solids (Vol. Ill)... 

The new era in physics started in 1900 with a young German physicist named Max Planck. While analyzing the data on radiation emitted by solids heated to various temperatures, Planck discovered that atoms and molecules emit energy only in certain discrete quantities, or quanta. Physicists had always assumed that energy is continuous and that any amount of energy could be released in a radiation process. Planck s quantum theory turned physics upside down. Indeed, the flurry of research that ensued altered our concept of nature forever. 

The photoelectric effect conld not be explained by the wave theory of light. Einstein, however, made an extraordinary assumption. He snggested that a beam of light is really a stream of particles. These particles of light are now called photons. Using Planck s quantum theory of radiation as a starting point, Einstein deduced that... 

Briefly explain Planck s quantum theory and explain what a quantum is. What are the units for Planck s... 

Einstein f succeeded in giving a qualitative explanation of this behaviour by applying Planck s quantum theory to the oscillations of atoms about their equilibrium position. If this hypothesis be applied to each individual atom, and it be assumed that if v is the oscillation frequency of the atom, the latter can only take up the quantum c = hv, or a whole multiple of it, we obtain... 

He was awarded the Nobel Prize in physics in 1921A.D. for applying Planck s Quantum Theory to the explanation of the photoelectric emission of electrons. 

To explain the photoelectric effect, Einstein assumed that the radiant energy striking the metal surface behaves like a stream of tiny energy packets. Each packet, which is like a particle of energy, is called a photon. Extending Planck s quantum theory. 

In 1916, Lewis was expressing his criticism for the recent atomic model proposed by Niels Bohr, based on the Max Planck s quantum theory, which assumed the atomic system as composed of fixed spherical orbits, so quantified - because, Lewis argued that, the spherical atomic system contains electrons whose motion is insensitive to the action of the external chaiges . 

Planck s Quantum Theory To explain the dependence of radiation emitted by objects on wavelength, Planck proposed that atoms and molecules could emit (or absorb) energy in discrete quantities called quanta. Planck s theory revolutionized physics. 

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