ATOM BOMB, QUANTUM MECANIC, MODERN ATOM THEORY

 

Actually, expressing matter is not that simple. It is best to use simple recipes that you remember from elementary school. Matter is anything that has mass and volume. We know a lot about matter. For example, it has four states: solid, liquid, gas, and plasma. It is made up of atoms. Since ancient times, it has been assumed that matter consists of atoms. If you cut a board in half, both pieces become boards. As long as we keep dividing the pieces, they will always be wood. We have two options here. To accept that matter can be divided forever, or to assume that there is one or more elementary particles that make up matter. According to an idea developed in ancient Greece, matter had basic building blocks that could no longer be divided, and these components were called "atoms", meaning "undivided." Until the beginning of the 21st century, Until the time when the existence of atoms was experimentally proven, some scientists believed in the existence of atoms and some did not. Today, with the electron microscope, we can see an atom with a magnification of 10 million times. We also know that atoms can separate and combine to form molecules. In fact, fission and fusion of atomic nuclei release enormous amounts of energy. When the star burns, the atomic nuclei coalesce and the heavy nuclei are destroyed by uranium and plutonium bombs. Fission and fusion of atomic nuclei release enormous amounts of energy. When the star burns, the atomic nuclei coalesce and the heavy nuclei are destroyed by uranium and plutonium bombs. Fission and fusion of atomic nuclei release enormous amounts of energy. When the star burns, the atomic nuclei coalesce and the heavy nuclei are destroyed by uranium and plutonium bombs.

Thanks to Einstein's famous formula E=mc2, we know the energy equivalent of matter. From all this we learn that neither atoms nor elementary particles exist. Atoms are made up of particles such as electrons, protons, and neutrons. Electrons cannot be further divided as elementary particles, and protons and neutrons are not the elementary particles that make up the nucleus of an atom, but there are elementary particles that compose them. These are called quarks and gluons. Before we move on to these fundamental particles, we need to answer another question.

Since there are many different substances, we can assume that there are many different atoms that make up these substances. There are 115 elements in the periodic table today, from the element hydrogen, 92 of which are natural elements, to the non-percentile found in 2013. This is the elements, not counting the isotopes. same number of protons and different number of neutrons, there are at least 92 different atoms in nature. In fact, a very important part of the matter in the universe is the simplest atom, the hydrogen atom. Although there are about 60 elements in the periodic table in the human body, most of them are traces, for example the fluorine atoms necessary for our teeth are only 37 parts per million cubic meters. Our body mass consists of 65% oxygen, 18% carbon, 10% hydrogen, 3% nitrogen. So what sets the atoms apart so much? To do this, we need to know the parts that make up the atom. After all,

It is difficult to get an idea of ​​the nature of matter by studying solids. Therefore, research in this field, which we can consider scientifically in the modern sense, starts from the air around us. In the 17th century, the properties of air began to be understood. Evangelista Toricelli invented the mercury barometer. It is an important measurement tool. Robert Boyle invented the concept of pressure. Boyle and Mariotte discovered that the product of pressure and volume is constant for all gases kept at a constant temperature (pxv = constant). Daniel Bernoulli treats gases as small balls to explain Boyle Mariotte's law and shows that the pressure product is theoretically constant. This is a very important development. We call the kinetic theory to explain the macroscopic properties of gases, such as their pressure, by the movement of gaseous atoms and molecules in this way.

Another concept that scientists were trying to understand was heat. It was once thought to be a fluid called "calorie" surrounding an object, like the atmosphere. According to the theory at the time, this invisible liquid consisted of "particles" repelling each other. Therefore, the material remaining in the device itself cools over time. 18 18 In the 19th century, scientists began to study the properties of caloric liquids. For example, if the caloric liquid has mass, the heated object must be heavier. But experiments have shown that the opposite is true: heating does not make an object heavier, and cooling does not make it lighter. Thus, the claim that heat is a substance began to be questioned.

As a result of his experiments in 1847, Joule showed that heat is a measure of the motion of matter, not matter. Jules found very important results in this regard. This got a lot of attention during the Industrial Revolution. The kinetic energy is converted into heat, but the total energy is always conserved. This important result, achieved in the 19th century, shattered the dreams of many hobby inventors. It was impossible to generate energy or create a circulatory system. The total energy in the system is always conserved and could not be destroyed or produced. The energy was just changing. Gradually, a universal law was discovered. These are now called "laws of thermodynamics". Clausius introduced the concept of entropy in 1865. The physical process has never lessened the confusion that the system is left to itself. The ice was orderly, the water more disordered, and the steam much more irregular. Of course, water turns into ice in the refrigerator, reducing roughness! However, when the refrigerator heats the kitchen air, electrical energy is distributed to the molecules in the room and the overall entropy or disorder increases.

In 1879, Maxwell and Boltzmann thought that "just as we can understand gas pressure in terms of the collision of gas molecules with the wall of the container in which the gas is placed, we can also understand other thermodynamics." The quantities below it understand the motion of the molecule." For example, temperature corresponds to the average kinetic energy of a gas molecule. In other words, when I say "this space is too hot," I am not satisfied that the average kinetic energy of the gas is high. So Boltzmann decided to understand entropy too. Thermodynamics He found that a system in equilibrium is the most chaotic possible, and that this chaotic system results from a set of states (microstates) in which the parts that make up the system are in the example of a molecule or atom. If this is true, a constant increase in entropy is not an absolute necessity, Statistically most likely. For example, odor molecules in a cologne bottle opened in a room spread around the room at an average speed of 500 m/s in a short time, increasing the congestion. This is what Clausius and the second law of thermodynamics predict. According to Boltzmann, the probability of all scent molecules returning to the bottle is not zero. Very low, but not zero. As a result, entropy is usually increasing, but may be decreasing. Planck dislikes Boltzmann's ideas and believes he can prove, as an absolute rule, that entropy always increases. To this end, it begins with the study of blackbody radiation. However, this study will have unpredictable results. It spreads around the room at a speed of 1 This is what Clausius and the second law of thermodynamics predict. According to Boltzmann, the probability of all scent molecules returning to the bottle is not zero. Very low, but not zero. As a result, entropy is usually increasing, but may be decreasing. Planck dislikes Boltzmann's ideas and believes he can prove, as an absolute rule, that entropy always increases. To this end, it begins with the study of blackbody radiation. However, this study will have unpredictable results. It spreads around the room at a speed of 1 This is what Clausius and the second law of thermodynamics predict. According to Boltzmann, the probability of all scent molecules returning to the bottle is not zero. Very low, but not zero. As a result, entropy is usually increasing, but may be decreasing. Planck dislikes Boltzmann's ideas and believes that he can prove, as an absolute rule, that entropy always increases. To this end, it begins with the study of blackbody radiation. However, this study will have unpredictable results. He dislikes these ideas and believes that as an absolute rule he can prove that entropy always increases. To this end, it begins with the study of blackbody radiation. However, this study will have unpredictable results. He dislikes these ideas and believes that as an absolute rule he can prove that entropy always increases. To this end, it begins with the study of blackbody radiation. However, this study will have unpredictable results.

Chapter 3: The Birth of Quantum Physics

As mentioned in the previous section, quantum physics is a continuation of thermodynamics, which was discovered in the 19th century and played an important role in the Industrial Revolution. In the late 19th century, Planck tackled a seemingly simple problem. The problem was this: All objects with radiation emitted from heat, but the distribution of this emitted radiation according to wavelength could not be explained by the classical physics rules. Wherever a person stands, he emits about 100 watts of electromagnetic waves. Most of this wave is in the microwave range, so you can't see it with the naked eye, but you can see it with an infrared camera.

BLACK OBJECT AND BLACK OBJECT RADIATION

Gustav Kirchhoff, one of the grandfathers of quantum physics, spent most of his time in the 1850s trying to understand the color changes of objects heated in an oven. For example, when the iron was heated, it first appeared red, then orange, and then bright (bright or blue). Kirchhoff was interested in the physical mechanism behind this color change. During his research, he discovered something very important. The better the object absorbs the light it hits (that is, does not reflect it directly like a mirror), the better it emits light. So a good absorber was also a good emitter! Kirchhoff envisioned an ideal object. Consider an object that absorbs all the light that hits it, does not reflect it at all, and emits it again as radiation.

Kirchhoff named this object a "blackbody" because it absorbs all the light that hits it.

A black body is an ideal body that absorbs light perfectly and emits light that is eventually absorbed as radiation of all wavelengths. Kirchoff showed that the spectrum of a black body, regardless of its shape and material from which it is made, depends only on its temperature. So we only know the temperature

It is possible to know at which wavelength and how much energy the object will emit. Kirchoff posed a crucial question to both experimental and theoretical physicists in 1859: How does the energy emitted by a black body per second change as a function of temperature and step wave? We can think of a blackbody like this: a closed box with a very small hole in it. This hole absorbs all the light that hits it. After the light falls inside the box, it will be absorbed by the walls. The inside of the box is filled with radiation at the same temperature as the wall of the box. So the radiation escapes through the hole. Experimental physicists immediately began measuring the radiation they emit when they heated objects. They were able to measure shorter wavelengths day after day. After nearly forty years of study, the black body radiation curve emerged. Unfortunately,

To keep in mind, we can roughly imagine a black object like this: Imagine a building whose windows look black from afar in the midday heat of summer. Because the light hitting the glass collides with the atoms or molecules in that part and is absorbed. However, the walls of the room emit electromagnetic waves, intense infrared rays at a certain temperature, and these waves are emitted through the glass. Here, glass is a good example of a black object.

Experimental physicists did Kirchoff's homework and, after much toil, discovered the blackbody radiation curve, but theoretical physicists lagged behind a bit. When electromagnetic theory, which is also the theory of light, is applied to the black body problem, we encounter a different curve both in the infrared region (microwave part) and in the ultraviolet region, and we encounter the curve revealed by experiment. While these experiments were being carried out, Planck was teaching from the podium that Kirchoff had left, in the right place where the experiments were being conducted in Berlin. He used the laws of thermodynamics to explain the light spectrum of black bodies. One thing he knew for sure: The radiation emitted by an object was due to the acceleration of charges within the object. That's what Maxwell said, and Hertz proved it, and that's how the radio was invented. However, to explain the blackbody curve, the micro-radiators that make up the blackbody are not intended to be dispersed at all frequencies. Maxwell would have objected if he had lived, but to explain the blackbody curve, Planck conceded that extremely small objects could only emit radiation at frequencies equal to multiples of their natural oscillation frequencies. The photon was born even when Planck was no longer aware of it.

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