THERMAL PHYSICS RALPH BAIERLEIN PDF
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Thermal Physics book. Read 3 reviews from the world's largest community for readers. Suitable for both undergraduates and graduates, this textbook provid. Read "Thermal Physics" by Ralph Baierlein available from Rakuten Kobo. Sign up today and get $5 off your first purchase. Clear and reader-friendly, this is an. Mar 28, Click here for the solutions in pdf format. Hard copies of the final exam solutions are Required Textbook. Thermal Physics, by Ralph Baierlein.
What are the common characteristics of these diverse means of heating and cooling? The following provides a partial list. There is net transfer of energy to or from the system, be it frying pan or muffin or soda. The amount of energy transferred may be controlled and known at the macroscopic level but not at the microscopic level.
The transfer of energy does not require any change in the system's external parameters.
The phrase "external parameters" is new and needs explanation, best given in the context of physics applications rather than a kitchen or picnic.
If steam is confined to a hollow cylinder fitted with a movable piston, then the volume Fof the container is an external parameter for the gas. For a piece of soft iron wrapped with many turns of current-carrying wire, the magnetic field produced by the electric current is an external parameter.
For a crystal of barium titanate between the plates of a capacitor, the electric field produced by the charges on the plates is an external parameter. In general, any macroscopic environmental parameter that appears in the microscopic mechanical expression for the energy of an atom or electron is an external parameter.
If you are familiar with quantum mechanics, then a more precise definition of an external parameter is this: In a fundamental way, one distinguishes two modes of energy transfer to a physical system: To be sure, both kinds of transfer may occur simultaneously for example, if one irradiates a sample at the same time that one changes the external magnetic field , but the distinction remains absolutely vital.
Energy transfer produced by a change in external parameters is called work. Again, if you are familiar with quantum mechanics, you may wonder, how would heating be described in the Schrodinger equation? Consider the muffin that is being toasted.
The Schrodinger equation for the muffin must contain terms that describe the interaction of organic molecules with the incident electromagnetic waves. But those terms fluctuate rapidly and irregularly with time; at most one knows some average value, perhaps a root mean square value for the electromagnetic fields of the waves. Although it may be well-defined at the macroscopic level, energy transfer by heating is inherently irregular and messy at the microscopic level.
Later, in chapter 14, this insight will prove to be crucial. For heating by conduction, literal contact is required. For heating by radiation, only a path for the electromagnetic radiation to get from one object to the other is required.
Elementary physics often speaks of three ways of heating: You may wonder, why is convection not mentioned here? Convection is basically energy transport by the flow of some material, perhaps hot air, water, or liquid sodium. Such "transport" is distinct from the "transfer" of energy to a physical system from its environment. For our purposes, only conduction and radiation are relevant.
To summarize: Temperature We return to the kitchen. In colloquial language, the red-hot coil on the stove is hotter than was the copper-bottomed pan while it hung on the pot rack. In turn, the eggs, as they came out of the refrigerator, were colder than the pan was. Figure 1. We can order objects in a sequence that tells us which will gain energy and which will lose energy by heating when we place them in thermal contact.
Of two objects, the object that loses energy is the "hotter" one; the object that gains energy is the "colder" one.
Thermal Physics: Newtonian Dynamics, and Newton to Einstein: The Trail of Light
Temperature is hotness measured on some definite scale. That is, the goal of the "temperature" notion is to order objects in a sequence according to their "hotness" and to assign to each object a number—its temperature— that will facilitate comparisons of "hotness.
Over the centuries, many ways have been found to achieve the ordering. The length of a fine mercury column in glass constitutes a familiar thermometer, as does the length of an alcohol column dyed red in glass. In a professional laboratory, tempera- ture might be measured by the electrical resistance of a commercial carbon resistor, by the vapor pressure of liquid helium, by the voltage produced in a copper-constantan thermocouple, by the magnetic susceptibility of a paramagnetic salt such as cerium magnesium nitrate, or by the spectral distribution of the energy of electromagnetic waves, to name only five diverse methods.
Calibration to an internationally adopted temperature scale is an item that we take up in section 4. Colder Hotter than pan than pan. The broad arrows indicate the direction of energy flow when the objects are placed in thermal contact. Return for a moment to the club picnic mentioned earlier. If you put a can of warm soda into the tub of water and crushed ice, the soda cools, that is to say, energy passes by conduction from the soda through the can's aluminum wall and into the ice water.
In the course of an hour or so, the process pretty much runs its course: One says that the soda has come to "thermal equilibrium" with the ice water. More generally, the phrase thermal equilibrium means that a system has settled down to the point where its macroscopic properties are constant in time. Surely the microscopic motion of indivi- dual atoms remains, and tiny fluctuations persist, but no macroscopic change with time is discernible.
We will have more to say about temperature later in this chapter and in other chapters. The essence of the temperature notion, however, is contained in the first paragraph of this subsection. The paragraph is so short that one can easily under- estimate its importance; I encourage you, before you go on, to read it again. As you read this, the air around you constitutes a dilute gas.
The molecules of diatomic nitrogen and oxygen are in irregular motion. The molecules collide with one another as well as with the walls of the room, but most of the time they are out of the range of one another's forces, so that—in some computations—we may neglect those inter- molecular forces. Whenever we do indeed neglect the intermolecular forces, we will speak of an ideal gas. We will need several relationships that pertain to a dilute gas such as air under typical room conditions.
They are presented here. Pressure according to kinetic theory Consider an ideal gas consisting of only one molecular species, say, pure diatomic nitrogen. There are N such molecules in a total volume V. In their collisions with the container walls, the molecules exert a pressure.
How does that pressure depend on the typical speed of the molecules? Because pressure is force exerted perpendicular to the surface per unit area, our first step is to compute the force exerted by the molecules on a patch of wall area A. At' where p denotes momentum and where we read from right to left to compute the force produced by molecular collisions.
When the molecule strikes the wall, its initial x-component of momentum mvx will first be reduced to zero and will then be changed to —mvx in the opposite direction. The letter m denotes the molecule's rest mass. Only the velocity component vx transports molecules toward the wall; it carries them a distance vxAt toward the wall in time At. To hit the wall in that time interval, a molecule must be within the distance vxAt to start with. In a moment, we will correct for that temporary assumption.
Insert into equation 1. The product v2x appears, and we must average over its possible values. We can usefully relate that average to v2 , the average of the square of the speed.
Angular brackets, , denote an average. Another, analogous meaning will be explained later, when it is first used.
Because v2 equals the sum of the squares of the Cartesian components of velocity, the same equality is true for their averages:. Thus, denoting the pressure by P, we emerge with the relationship. The pressure is proportional to the average translational kinetic energy and to the number density. An empirical gas law In the span from the seventeenth to the nineteenth centuries, experiments gave us an empirical gas law:. The temperature T is the absolute temperature, whose unit is the kelvin, for which the abbreviation is merely K.
Precisely how the absolute temperature is defined will be a major point in later chapters. You may know a good deal about that topic already. For now, however, we may regard Tas simply what one gets by adding A brief history of this empirical gas law runs as follows. Gay-Lussac used literally mercury thermometers and the Celsius scale. By , Gay-Lussac had found that reacting gases combine in a numerically simple fashion. For example, one volume of oxygen requires two volumes of hydrogen for complete combustion and yields two volumes of water vapor all volumes being measured at a fixed pressure and temperature.
This information led Amadeo Avogadro to suggest in that equal volumes of different gases contain the same number of molecules again at given pressure and temperature. The empirical gas law, as displayed in 1. All the functional dependences were known and well-established before the first quarter of the nineteenth century was over. Our version of the empirical law is microscopic in the sense that the number TV of individual molecules appears.
Although data for a microscopic evaluation of the proportionality constant were available before the end of the nineteenth century, we owe to Max Planck the notation k and the first evaluation. To determine their numerical values, he compared his theory with existing data on radiation as will be described in section 6. Then, incorporating some work on gases by Ludwig Boltzmann, Planck showed that his radiation constant k was also the proportionality constant in the microscopic version of the empirical gas law.
Equation 1. Thus far, I have chosen to use the phrase "empirical gas law" to emphasize that equation 1. Although the relationship is accurate only for dilute gases, it is thoroughly grounded in experiment. As it enters our development, there is nothing hypothetical about it. So long as the gas is dilute, we can rely on the empirical gas law and can build on it. Nevertheless, from here on I will conform to common usage and will refer to equation 1. Average translational kinetic energy Both kinetic theory and the ideal gas law provide expressions for the pressure.
Those expressions must be numerically equal, and so comparison implies. To be sure, we must note the assumptions that went into this derivation. In working out the kinetic theory's expression for pressure, we assumed that the gas may be treated by classical Newtonian physics, that is, that neither quantum theory nor relativity theory is required.
Moreover, the ideal gas law fails at low temperatures and high densities. Some of these criteria will be made more specific later, in chapters 5 and 8. The microscopic view of matter where the "matter" might be a gas of diatomic oxygen sees matter as a collection of atomic nuclei and electrons.
The gas can possess energy in many forms: There can also be energies associated with the motion and location of the center of mass CM of the entire gas: Usually the energies associated with the center of mass do not change in the processes we consider; so we may omit them from the discussion. Rather, we focus on the items in the displayed list and others like them , which-collectively—constitute the internal energy of the system.
The internal energy, denoted by E9 can change in fundamentally two ways: If particles are permitted to enter and leave what one calls "the system," then their passage may also change the system's energy. In the first five chapters, all systems have a fixed number of particles, and so—for now—no change in energy with particle passage need be included. An infinitesimal change AE in the internal energy is connected to items 1 and 2 by conservation of energy: For sound historical reasons, equation 1.
The word thermodynamics itself comes from "therme," the Greek word for "heat," and from "dynamics," the Greek word for "powerful" or "forceful. Indeed, a year-old William Thomson, later to become Lord Kelvin, coined the adjective "thermodynamic" in in a paper on the efficiency of steam engines. We need a way to write the word equation 1.
The lower case letter q will denote a small or infinitesimal amount of energy transferred by heating; the capital letter Q will denote a large or finite amount of energy so transferred.
Thus the First Law becomes.
Donald M. Eigler and Erhard K. Schweizer moved the 35 atoms into position on a nickel surface with a scanning tunneling microscope and then "took the picture" with that instrument. The work was reported in Nature in April When thermodynamics was developed in the nineteenth century, the very existence of atoms was uncertain, and so thermodynamics was constructed as a macroscopic, phenomenological theory.
Today we can safely build a theory of thermal physics on the basis of atoms, electrons, nuclei, and photons. By the way, xenon atoms are not shaped like chocolate kisses; the conical appearance is an artifact of the technique. Eigler and E. Schweizer, "Positioning single atoms with a scanning tunnelling microscope," Nature , 5 April Also, D. Eigler, private communication. A further remark about notation is in order. The symbol A always denotes "change in the quantity whose symbol follows it.
But, at other times, A may denote a large or finite change in some quantity. One needs to check each context. The detailed expression for work done by the system depends 1 on which external parameter changes and 2 on whether the system remains close to thermal equilibrium during the change. Let us consider volume Fand the pressure exerted by a gas in a hollow cylinder with a movable piston, as sketched in figure 1.
For the small increment A V in volume, accomplished by slow expansion, the work done by the gas is this: The last line follows because the volume change AV equals the cross-sectional area times the distance through which the piston moves. The cylindrical shape helps us to derive the PA V form, but the expression is more general and holds for any infinites- imal and slow change in volume. Thus, for a slow expansion, the First Law of Thermodynamics now takes the form.
If we heat a dilute gas at constant volume, the molecules experience an increase in their average translational kinetic energy. The correlation of heating and temperature change is usefully captured in a ratio: Thus the generic expression is this: Using equations 1. Because all external parameters are held constant, no work is done, and so 1.
When a limit of infinitesimal transfer is taken, a partial derivative is required because we stipulate that the variation of internal energy with temperature is to be computed at constant external parameters; that is made explicit with paren- theses and a subscript V. Succinctly, think of E as a function of T and V: If the gas is monatomic and if equation 1.
As defined above, the heat capacity refers to the entire system. Such expressions give a heat capacity per unit mass or per particle. The expressions are called specific heats. There is nothing intrinsically new in them. Those quantities are merely more useful for tabulating physical properties and for comparing different materials.
Heat capacity at constant pressure If a gas may expand while being heated but is kept at a constant pressure, the associated heat capacity—the heat capacity at constant pressure—is denoted Cp. Again using equations 1.
The quotients are easy to evaluate for an ideal gas which may have polyatomic molecules under conditions of temperature and number density such that the ideal gas law holds. We will call such a gas a classical ideal gas. The second term in the numerator of 1.
In the absence of intermolecular forces and when temperature and number density are such that the ideal gas law holds, the internal energy E depends on T9 TV, and the molecular species, but not on the volume.
In short, equation 1. The heat capacity is larger now because some energy goes into doing work as the gas is heated and expands. The mole Tucked in here are a few paragraphs about the mole. To an accuracy of 1 percent, a mole of any isotope is an amount whose mass, measured in grams, is equal to the sum of the number of protons and neutrons in the isotope's nucleus.
Rigorously, a mole of any isotope or naturally occurring chemical element is an amount that contains the same number of atoms as there are in 12 grams of the isotope 12 C, that is, the carbon atom that has six protons and six neutrons. A mole of a molecular species, such as water H2O or carbon dioxide CO2 , is an amount that contains NA molecules of the species.
The etymology of the word "mole" is curious and may help you to understand the use in physics and chemistry. According to the Oxford English Dictionary, the Latin word moles means "mass" in the loose sense of a large piece or lump of stuff.
In the seventeenth century, the Latin diminutive molecula spawned the English word "mol- ecule," meaning a small or basic piece. In , the German chemist Wilhelm Ostwald lopped the "cule" off "molecule" and introduced the mole or mol in the sense defined two paragraphs back. The ideal gas law can be expressed in terms of the number of moles of gas, and that version is common in chemistry.
To see the connection, multiply numerator and denominator of equation 1. The form of the First Law, as expressed in equation 1. In the preceding section we saw one of those extremes: The opposite extreme consists of no heating but some work done. That is, in an adiabatic process, no energy goes through an interface by heating or cooling. If the adiabatic process occurs slowly, some work is sure to be done. If the process occurs rapidly, for example, as an expansion into a vacuum, it may be that no work is done on the environment.
Another contrast is often made: The latter is called an isothermal process, for the adjective "isothermal" means "at constant temperature" or "for equal temperatures. The adiabatic relation for a classical ideal gas Consider a classical ideal gas. The gas's internal energy, however, does not change. In an expansion under adiabatic conditions, the internal energy drops because the gas does work on its surroundings but no energy input by heating is available to compen- sate. Thus the temperature drops.
Consequently, in an adiabatic process, two factors cause the pressure to drop—an increase in volume and a decrease in temperature—and so the pressure drops faster. To calculate the isothermal curve in figure 1.
For the adiabatic process, there must be an analogous supplementary relation. To derive it, we return to the First Law of Thermodynamics, equation 1. Each integration will produce a logarithm. Both tradition and convenience suggest expressing Nk as the difference of two heat capacities; by 1. The constancy of the right-hand side implies that the argument of the logarithm remains constant:. This equation relates final and initial values of T and V during an adiabatic change of volume:.
The stipulation of no energy transfer by heating constrains the triplet T9 P, and V more than the ideal gas law alone would and hence generates the additional relationship 1. Precisely because the ideal gas law continues to hold, we may use it to eliminate T in 1. The new form of what is really the same relationship becomes.
This expression seems to be the easiest to remember. Starting from here, we recover equation 1. Elimination of V from 1. It suffices to remember one form and to know that you can get the others by elimination. The expansion of a warm, low density cloud as it rises in the sky is approximately an adiabatic process.
Consequently, its tempera- ture drops, and more moisture condenses.
How general are the relationships 1. We specified a classical ideal gas and a slow process, so that the system remains close to thermal equilibrium. Those are two restrictions. Beyond that, the step from 1. Often that assumption is a good approximation. For example, it is fine for diatomic oxygen and nitrogen under typical room conditions.
If the temperature varies greatly, however, Cy will change; sections If you glance back through the chapter, from its opening paragraph up to equation 1. Historically, the word "heat" has been used as a noun as well, but such use— although common—is often technically incorrect.
The reason is this: In sequence a , hot steam doubles in volume as it expands adiabatically into a vacuum. Because the water molecules hit only fixed walls, they always rebound elastically. The steam loses energy and also drops in temperature. To compensate for the energy loss, in the last stage a burner heats the water vapor, transferring energy by heating until the steam's energy returns to its initial value.
If a definite amount or kind of energy in the water vapor could be identified as "heat," then there would have to be more of it at the end of sequence b than at the end of sequence a , for only in sequence b has any heating occurred. But in fact, there is no difference, either macroscopic or microscopic, between the two final states.
An equivalent way to pose the problem is the following. The challenge is to identify a definite amount or kind of energy in a gas that 1 increases when the gas is heated by conduction or radiation and 2 remains constant during all adiabatic processes. No one has met that challenge successfully. Such a concept is untenable, as the analysis with figure 1. Such time is incorporated into the sequences.
The literal meaning of the phrase would be "capacity for holding heat," but that is not meaningful. The ratio in expression 1. From time to time, we will calculate a "heat capacity. Even the words "heating" and "cooling" are used in more than one sense. Thus far, I have used them exclusively to describe the transfer of energy by conduction or radiation.
The words are used also to describe any process in which the temperature rises or drops. Thus, if we return to figure 1. If one were to push the piston back in and return the gas to its initial state, one could describe that process as "heating by adiabatic compression" because the temperature would rise to its initial value. In both cases the adjective "adiabatic" means "no cooling or heating by conduction or radiation," but the temperature does change, and that alone can be the meaning of the words "cooling" and "heating.
For a moment, imagine that you are baby-sitting your niece and nephew, Heather and Walter, as they play at the beach. The 4-year-olds are carrying water from the lake and pouring it into an old rowboat. When you look in the rowboat, you see clear water filling it to a depth of several centimeters. While Heather is carrying water, you can distinguish her lake water from Walter's— because it is in a green bucket—but once Heather has poured the water into the rowboat, there is no way to distinguish the water that she carried from that which Walter poured in or from the rainwater that was in the boat to start with.
The same possibilities and impossibilities hold for energy transferred by heating, energy transferred by work done by or on the system , and internal energy that was present to start with.
Energy that is being transferred by conduction or radiation may be called "heat. Once such energy has gotten into the physical system, however, it is just an indistinguishable contribution to the internal energy.
Only energy in transit may correctly be called "heat. Beyond that, thermodynamics notes that some of those attributes can be calculated from others for example, via the ideal gas law. Such attributes are called state functions because, collectively, they define the macroscopic state and are defined by that state. As we reasoned near the beginning of this section, one may not speak of the "amount of heat" in a physical system. These are subtle, but vital, points if one chooses to use the word "heat" as a noun.
In this book, I will avoid the confusion that such usage invariably engenders and will continue to emphasize the process explicitly; in short, I will stick with the verb-like forms and will speak of "energy input by heating.
It is neither. Historical usage, however, cannot be avoided, especially when you read other books or consult collections of tabulated physical properties. Stay alert for misnomers.
While we are on the subject of meanings, you may wonder, what is "thermal physics"? Broadly speaking, one can define thermal physics as encompassing every part of physics in which the ideas of heating, temperature, or entropy play an essential role. If there is any central organizing principle for thermal physics, then it is the Second Law of Thermodynamics, which we develop in the next chapter.
This section collects essential ideas and results from the entire chapter. It is neither a summary of everything nor a substitute for careful study of the chapter. Its purpose is to emphasize the absolutely essential items, so that—as it were—you can distinguish the main characters from the supporting actors. Think of heating as a process of energy transfer, a process accomplished by conduction or radiation.
No change in external parameters is required. Whenever two objects can exchange energy by heating or cooling , one says that they are in thermal contact.
Any macroscopic environmental parameter that appears in the microscopic mech- anical expression for the energy of an atom or electron is an external parameter.
Volume and external magnetic field are examples of external parameters. Pressure, however, is not an exteijial parameter. That is, the goal of the "temperature" notion is to order objects in a sequence according to their "hotness" and to assign to each object a number—its temperature—that will facilitate comparisons of "hotness.
The phrase thermal equilibrium means that a system has settled down to the point where its macroscopic properties are constant in time. Surely the microscopic motion of individual atoms remains, and tiny fluctuations persist, but no macroscopic change with time is discernible.
When the conditions of temperature and number density are such that a gas satisfies the ideal gas law, we will call the gas a classical ideal gas. The shorter phrase, ideal gas, means merely that intermolecular forces are negli- gible. The questions of whether classical physics suffices or whether quantum theory is needed remain open.
The First Law of Thermodynamics is basically conservation of energy: A general definition of heat capacity is the following: Thus the last expression is not general. A process in which no heating occurs is called adiabatic. Attributes that, collectively, define the macroscopic state and which are defined by that state are called state functions. Examples are internal energy E, temperature T, volume V, and pressure P. One may not speak of the "amount of heat" in a physical system.
Max Planck introduced the symbols h and k in his seminal papers on blackbody radiation: Leipzig 4, and Thomas S. Kuhn presents surprising historical aspects of the early quantum theory in his book, Black- body Theory and the Quantum Discontinuity, Oxford University Press, New York, Zemansky in The Physics Teacher 8, Appendix A provides physical and mathematical data that you may find useful when you do the problems.
A fixed number of oxygen molecules are in a cylinder of variable size. Someone compresses the gas to one-third of its original volume. Simultaneously, energy is added to the gas by both compression and heating so that the temperature increases five fold: The gas remains a dilute classical gas. By what numerical factor does each of the following change: Be sure to show your line of reasoning for each of the three questions.
Radiation pressure. Adapt the kinetic theory analysis of section 1. There are TV photons, each of energy hv, where h is Planck's constant and v is a fixed frequency. The volume V has perfectly reflecting walls. Express the pressure in terms of N, V, and the product hv.
Section 6. Relativistic molecules.
Suppose the molecules of section 1. Suppose also that the molecules survive collision with the wall! Eliminate the speed v entirely. If you know the pressure exerted by a photon gas, compare the limit here with the photon gas's pressure.
Adiabatic compression. A diesel engine requires no spark plug. Rather, the air in the cylinder is compressed so highly that the fuel ignites spontaneously when sprayed into the cylinder. For air, the ratio of heat capacities is y — 1.
Adiabatic versus isothermal expansion.
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In figure 1. Ruchardts experiment: You take a stainless steel sphere of radius ro and lower it— slowly—down the tube until the increased air pressure supports the sphere. Assume that no air leaks past the sphere an assumption that is valid over a reasonable interval of time and that no energy passes through any walls.
Determine the distance below the tube's top at which the sphere is supported. Provide both algebraic and numerical answers. You have determined an equilibrium position for the sphere while in the tube. Numerical data: Take the ratio of heat capacities to lie in the range 1. Ruchardt's experiment: This question carries on from "Ruchardt's experiment: In your quantitative calculations, ignore friction with the walls of the tightly fitting tube, but describe how the predicted evolution would change if you were to include friction.
Note that the equilibrium location for the "lowered" ball is about half-way down the tube. After you have worked things out algebraically, insert numerical values. Present an expression for y in terms of the oscillation frequency together with known or readily measurable quantities. A monatomic classical ideal gas of N atoms is initially at temperature 7b in a volume Vo. The gas is allowed to expand slowly to a final volume 7Fo in one of three different ways: For each of these contexts, calculate the work done by the gas, the amount of energy transferred to the gas by heating, and the final temperature.
Express all answers in terms of N9 7b, VQ9 and k. Chapter 2 examines the evolution in time of macroscopic physical systems. This study leads to the Second Law of Thermodynamics, the deepest principle in thermal physics. To describe the evolution quantitatively, the chapter introduces and defines the ideas of multiplicity and entropy. Their connection with temperature and energy input by heating provides the chapter's major practical equation. Simple things can pose subtle questions. A bouncing ball quickly and surely comes to rest.
Why doesn't a ball at rest start to bounce? There is nothing in Newton's laws of motion that could prevent this; yet we have never seen it occur. If you are skeptical, recall that a person can jump off the floor. Similarly, a ball could—in principle—spontaneously rise from the ground, especially a ball that had just been dropped and had come to rest.
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Or let us look at a simple experiment, something that seems more "scientific. When the clamp is opened, the bromine diffuses almost instantly into the evacuated flask. The gas fills the two flasks about equally. The molecules seem never to rush back and all congregate in the first flask.
You may say, "That's not surprising. Want to Read Currently Reading Read. Other editions. Enlarge cover. Error rating book. Refresh and try again. Open Preview See a Problem? Details if other: Thanks for telling us about the problem. Return to Book Page. Preview — Thermal Physics by Ralph Baierlein. Thermal Physics by Ralph Baierlein. Suitable for both undergraduates and graduates, this textbook provides an up-to-date, accessible introduction to thermal physics.
The material provides a comprehensive understanding of thermodynamics, statistical mechanics, and kinetic theory, and has been extensively tested in the classroom by the author who is an experienced teacher. This book begins with a clear review Suitable for both undergraduates and graduates, this textbook provides an up-to-date, accessible introduction to thermal physics.
This book begins with a clear review of fundamental ideas and goes on to construct a conceptual foundation of four linked elements: This foundation is used throughout the book to help explain new topics and exciting recent developments such as Bose-Einstein condensation and critical phenomena.
The highlighting of key equations, summaries of essential ideas, and an extensive set of problems of varying degrees of difficulty will allow readers to fully grasp both the basic and current aspects of the subject. A solutions manual is available for instructors.
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This book is not yet featured on Listopia. Community Reviews. Showing Rating details. Then, incorporating some work on gases by Ludwig Boltzmann, Planck showed that his radiation constant k was also the proportionality constant in the microscopic version of the empirical gas law. Equation 1.
Thus far, I have chosen to use the phrase "empirical gas law" to emphasize that equation 1. Although the relationship is accurate only for dilute gases, it is thoroughly grounded in experiment. As it enters our development, there is nothing hypothetical about it. So long as the gas is dilute, we can rely on the empirical gas law and can build on it. Nevertheless, from here on I will conform to common usage and will refer to equation 1.
Those expressions must be numerically equal, and so comparison implies 1.
In working out the kinetic theory's expression for pressure, we assumed that the gas may be treated by classical Newtonian physics, that is, that neither quantum theory nor relativity theory is required. Moreover, the ideal gas law fails at low temperatures and high densities. Some of these criteria will be made more specific later, in chapters 5 and 8.
There can also be energies associated with the motion and location of the center of mass CM of the entire gas: translational kinetic energy of the CM, kinetic energy of bulk rotation about the CM, and gravitational potential energy of the CM, for example.
Usually the energies associated with the center of mass do not change in the processes we consider; so we may omit them from the discussion. Rather, we focus on the items in the displayed list and others like them , which-collectively—constitute the internal energy of the system. The internal energy, denoted by E9 can change in fundamentally two ways: 1. If particles are permitted to enter and leave what one calls "the system," then their passage may also change the system's energy.
In the first five chapters, all systems have a fixed number of particles, and so—for now—no change in energy with particle passage need be included. For sound historical reasons, equation 1. The word thermodynamics itself comes from "therme," the Greek word for "heat," and from "dynamics," the Greek word for "powerful" or "forceful.
Indeed, a year-old William Thomson, later to become Lord Kelvin, coined the adjective "thermodynamic" in in a paper on the efficiency of steam engines.
We need a way to write the word equation 1. The lower case letter q will denote a small or infinitesimal amount of energy transferred by heating; the capital letter Q will denote a large or finite amount of energy so transferred.
Thus the First Law becomes Figure 1. Donald M. Eigler and Erhard K. Schweizer moved the 35 atoms into position on a nickel surface with a scanning tunneling microscope and then "took the picture" with that instrument.There's a problem loading this menu right now.
Chapter 2 examines the evolution in time of macroscopic physical systems. Quantum Mechanics in Chemistry. Thermal Physics by Ralph Baierlein. Note that there is no chemical reaction with the helium. If particles are permitted to enter and leave what one calls "the system," then their passage may also change the system's energy. Show the different spatial arrangements with sketches. This is a sobering consequence of the Second Law.