Understanding Relativity, Light, and Atomic Spectra
Two Simultaneous Events in Relativity
There will be two simultaneous events since there will be a dilation of mass, time, and length, ranging from relativistically. The only condition to produce this phenomenon is that the speed of the moving observer must be close to the speed of light.
Relativistic and Classical Physical Theories
Two physical theories are briefly described: relativistic and classical. The results are as follows:
- The corpuscular theory of light, explained through the Compton effect, states that light can behave like a particle and not just as a wave.
- The speed of light is constant and does not need any medium to transport; it travels through a vacuum.
Two Systems in Motion
Suppose two systems where only system O’ moves relative to O on the OX axis. Only in the position X’ is there a variation of O, as in speed, while the acceleration is zero in X’ and Y’/Z’ because the speed is constant and there is no velocity, respectively.
Postulates of Special Relativity
First postulate: The laws of physics are the same in all inertial frames. There is no privileged inertial reference system that can be considered absolute.
Second postulate: The speed of light in a vacuum is a universal constant that is independent of the movement of the light source.
Differences Between Classical and Modern Physics
- For classical physics, there was a single reference system, and everything was moving in that system, whereas in modern physics, there is no single reference system.
- In classical physics, the speed of light depended on the source emitter, while in modern physics, the value of light is always the same.
The Photoelectric Effect
The photoelectric effect is the emission of electrons from metals illuminated with light of a certain frequency. For each substance, there is a minimum frequency below which no photoelectrons are produced, no matter how intense the radiation is.
The Hydrogen Spectrum Explained
The hydrogen spectrum occurs because only one electron can move to different energy levels depending on the radiation that strikes the hydrogen atom. The energy spectrum is quantized.
Metal Surfaces and Light
- Blue light: If delivered, e– will be emitted because its wavelength, being lower than green, emits radiation with greater energy. This energy will be sufficient to eject the e– from the metal surface.
- Red light: Will not emit e– because its wavelength is larger than yellow.
De Broglie Hypothesis
De Broglie proposed that matter must also possess properties of both wave and particle. So far, electrons have been considered as particles and, therefore, were different from a wave. De Broglie proposed eliminating this distinction: a particle beam and a wave are essentially the same phenomenon, so the electron has a wavelength.
The Compton Effect Explained Briefly
When white light passes through a slit, it decomposes according to the different wavelengths. It deviates, and we see that what was obtained in the detector was not as expected.
Conclusion: Light behaves as both a wave and a particle.
The Hydrogen Atom and Energy Emission
It is true that when an atom receives energy to jump from one level to another, this energy is released, and it emits electromagnetic radiation that is seen in the spectrum. It depends on the energy that radiates to the hydrogen atom.