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Photons and matter

1) black Body:

Draft of an able body to totally become lean electromagnetic waves of any frequency. Small opening in one is come true carrying out one great cavity.

 

2) Formula of Rayleigh Jeans and ultraviolet catastrophe:

It turns out to you experiences them second which the intensity of the cancellation emitted from the black body held to T temperature in function of the wavelength has a course to bell, the classic theory but fails in how much obtains that for small wavelengths, the issued intensity would have to be infinite and this is called ultraviolet catastrophe.

 

3) Hypothesis of Planck :

In the cavity the energy exchange happens according to multiples of a how much elementary one that depend on the frequency through the relation.

 

4) external photoelectric Effect and interpretation of Einstein :

In a metal there are electrons that from there do not exit in how much the energy upgrade them are minor who not in the empty one, yielding but they this gap of energy, can estrarli. According to the classic theory that can happen sending sul to metal electromagnetic waves of one whichever frequency while the truth experiences them is that enough also a single photon of opportune frequency in order to extract an electron, Einstein explained the dilemma simply using the hypothesis of Planck that is asserting that the energy del photon incident depends gives it frequency and if it is not greater della barrier of upgrades them, the electron does not come extracted.

 

5) Problematic of electromagnetism classic in the comparisons of the atomic phantoms :

to)    the planetary model of Rutherford it has the problem that an electron that is found on a circular orbit must emit electromagnetic energy, but if ago, it will end for falling on the nucleus.

b)    the phantom of emission of atoms is not continuous but every atom emits determined solos frequencies given from the law of Rydberg.

 

6) Formula in order to gain the emitted spectral lines from an atom:

The frequency of the emitted spectral lines from an atom obeys to the relation where M and N is entire numbers and R is the constant of Rydberg.

 

7) Hypothesis of Bohr :

The hypothesis of Bohr previews the quantization of the angular moment and consequently of the beam of the orbit, the angular velocity and the energy total, that explains is the spectral lines that the fallen lacked one the electron on the nucleus.

 

8) fundamental State :

The fundamental state of an atom is that one to lower energy, more close to the nucleus.

 

9) Phenomenon of the diffraction of i beams X and interpretation :

The phenomena of the diffraction and the interference happen when the waves interact with geometric structures with characteristic dimensions similar to the wavelength incident, therefore as an example i beams x can be diffratti from the reticular plans, the condition that the wave must respect for being from they diffratta is being d the distance between the reticular plans and q the angle of incidence. The problems for the classic mechanics are born when against the material a wave is not sent but an endowed particle of mass as an electron and looks at that also it evidently gives place to phenomena of diffraction therefore to it must is associated a wave whose value is given from the law experiences them of De Broglie.

 

10) Relation of De Broglie :

De Broglie supports that the light has a double nature, to particellare and ondulatoria for which to an electron it is associated is one mass that a wave. The relation that alloy the wavelength l of the cancellation to its momentum .

 

11) physical Interpretation of the hypothesis of Bohr :

Replacing in the hypothesis of quantization of the angular moment of Bohr the hypothesis of De Broglie it is come to determine that the wavelength of the wave associated to the electron must be contained an entire number of times in the orbit of the electron, that is the wave must be stationary, only tipologia of wave that does not concur irradiation. Carrying out the reasoning backwards it is clearly that this is the cause of the quantization of the angular moment.

 

12) essential Property of every function that it represents a wave of any type :

Contemporary dependency from the time and the space must possess one.

 

13) Equation of Schroedinger :

It describes the function of wave y(x, y, z, t) that is the wave associated to one endowed particle of mass.

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It is reached to it through the following passages :

to)    the relation of a flat wave is written, derives respect to x, y, z and the relation of De Broglie is replaced in it , obtains therefore the operator to associate to the momentum . In analogous way it is derived regarding t the equation of a flat wave and it is replaced , obtaining the operator to associate to and .

b)    Being the energy of a free particle it does not make that to replace the operating ones of and and p, if then the particle is subject to conservative forces to energy upgrades them V replaces the operating ones in.

c)    applies the found total operator to the wave function.

 

14) Meant physicist of the wave function :

The module picture of the wave function y that is represents the density of presence of the particle in point x, y, z to the time t. Such density goes multiplied for one constant of normalization that renders unitarian the integreale calculated on all the space.

 

15) Principle of indetermination of Heisenberg :

It asserts that there are conjugated braces of variable for which when it increases the degree of acquaintance of one automatically diminishes the degree of acquaintance of the other, the brace of variable of interest in quantistica is the momentum and the position of the electron well Heisenberg asserts that dates the reduced dimensions of this particle, when we by means of a proton try to characterize of the position we know to have taken it but the photon yields to the electron energy and it sends it to blink goodness knows where. The principle of indetermination of Heisenberg asserts that the product of the uncertainties is worth .

 

16) Equation of independent Schroedinger from the time :

It is obtained replacing in the equation of Schroedinger the expression of a function of wave whose dependency from the time and the space is decomposable in the product of 2 functions, one employee from the position and the other employee from the space. It is apt to describe the stationary states.

 

17) quantici Numbers :

The equation of independent Schroedinger from the time is an equation to the autovalori that solution for some levels (n) of energy only admits and n . Moreover for some of sayings levels us they can be the solutions, well n and they are the quantici numbers of the wave equation.

 

18) Solution of the equation of Schroedinger in the free particle case :

The time is necessary to place V = 0 in the equation of independent Schroedinger and to limit itself to the unidimensionale case, is obtained :

 

19) Solution of the equation of Schroedinger in the case of hole of upgrades them to infinite walls :

for n equal and for n uneven is had.

In short it describes that between the 2 barriers of it upgrades them infinite are determined of the standing waves whose n° of nodes grows to growing of the energy of the stationary state.

 

20) Solution of the equation of Schroedinger in the case of hole of upgrades them to ended walls :

It is necessary to join together the solution within the hole of upgrades them that he is equal to the solution for infinite walls with the solution of the equation of Schroedinger outside from the hole, ci² that it is obtained have been stationary similar to those that are had for the hole to infinite walls, with the difference constituted from the effect Tunnel that is is possibility to find the particle outside from the hole of upgrades them also for the inferior energetic levels to the barrier of upgrades them.

 

21) Solution of the equation of Schroedinger for the unidimensionale harmonic oscillator :

Considering as energy all not degenerate states of energy are obtained.

 

22) Solution of the equation of Schroedinger for the hydrogen atom :

It is obtained replacing in the equation of Schroedinger as energy upgrades them , are come to determine the following quantici numbers :

n legacy to the energy of the state

l legacy to the module of the angular moment

m legacy to the projection of B on an axis

every energetic level is 2 l 1 degenerate times.

 

23) Spin, bosoni and fermions :

The spin it round describes a spin of the particle to a its axis of symmetry , are bosoni the particles for which the spin it is an entire one, like for the photon, while the particles are fermions for which the spin it is semintero, as for electrons and neutrons.

 

24) Principle of exclusion of Pauli :

Two particles to spin semintero cannot have the same quantici numbers, it is obtained before confronting the functions of wave of a system more particles and after the reversal of two of they.

 

25) Scope of statistics of Boltzmann, Firm, Bose:

They mean to describe the particle number that, for one given temperature, possesses one given energy. They are distinguished between they for the type of particle which they are applied.

 

26) Statistics of Boltzmann:

The particles are considered distinguibili, it extension naturally that many particles possess low energies while little particles possess high energies.

 

27) Statistics of Bose - Einstein :

The indistinguibilità of particles is prevailed in statistics of Boltzmann, finds that to low temperatures the overwhelming majority of the bosoni goes to occupy the state to minimal energy. For systems to low density it stretches statistics of Boltzmann.

 

28) Statistics of Firm - Dirac:

The indistinguibilità of particles is prevailed in statistics of Boltzmann, and the principle of exclusion of Pauli, obtains a distribution to step whose angles are dulled to growing of the temperature. For systems to low density it stretches statistics of Boltzmann.