- #1
Physics345
- 250
- 23
- Homework Statement
- The purpose of this assignment is to make connections between entropy, energy, and work. To achieve this, you will define energy and explain why it is useful to us. You will also discuss how engineers transform energy from the environment into forms useful for human endeavors. This will require that you explain both thermodynamics, and entropy. You will also outline each of the four laws and provide explanations and examples of each. You will then outline and define the four branches of thermodynamics. In this outline, you will include:
• a list of the methodological approaches used in conjunction with each branch,
• a list the theories associated with each branch,
• the contributions each branch makes to the understanding of thermodynamics,
• any perceived limitations to each of the branches, and
• an explanation of how entropy is understood/explained in each respective branch.
Your conclusion will summarize your key points and explain the importance of understanding thermodynamics in the contemporary world. As this paper is more of a report than an essay, an overt argument is not required
- Relevant Equations
- No equations required.
Hello everyone,
I have to write a paper about entropy and how it relates to the laws of thermodynamics, energy, and work. I have taken a deductive approach starting from the zero-th law to the second law of thermodynamics as follows.
Entropy is the disorder of a system (Class Video, 2019). To describe entropy, let’s begin by discussing what a system is. A system can be described as any mass which consists of molecules. A room, moon, planet, sun, galaxy, and the universe are all systems. They all comprise molecules but what drives these molecules to become disordered? Well, let’s think of boiling water, the system would be the pot that boils the water. As the water increases in temperature, the molecules begin to collide at a much faster rate, which implies an increase in entropy. When one closes their eyes and imagines millions of molecules colliding with one another, would they refer to this state as ordered or disordered? It would be disordered. For the molecules to be in order, they would need to halt their motion. Therefore, a state of order would be when molecules are no longer in motion, and a state of disorder is when the molecules are in motion. Then it also goes to say, that when heat is transferred, there is a disorder in a system and when the heat is not being transferred, there is order in a system. This means energy will always exist in the universe, but energy requires heat to be transferred from one body to another. Therefore, without heat being transferred in a system work cannot occur. Now that we have established what entropy is let’s continue by deducing how it relates to the laws of thermodynamics. We will begin with the zero-th law of thermodynamics which states “if two bodies are equal in temperature to a third, they are equal in temperature to each other” (Oakes, 2016, pg. 506). When one thinks of how the universe transfers heat, they will think of stars and radiation. Then how does the zero-th law and entropy relate to one another? When the universe reaches absolute zero, the zero-th law applies. If there is heat being transferred in the universe, then there will be disorder. If heat is no longer being transferred in the universe, then the universe will reach a state of order. All life will cease, to exist since all bodies within the universe will be equal in temperature, of absolute zero. This implies no heat is being transferred in the universe thus reaching a thermodynamic equilibrium. A thermodynamic equilibrium occurs “when the properties do not vary from point to point in a system and there is no tendency for change”. Following the definition, we can conclude that this is an isothermal process. This means that the surface temperature is constant, the ambient temperatures are constant. Therefore, all temperatures are equal to absolute zero. This implies the energy being transferred during thermodynamic equilibrium should equal zero, when heat is no longer being transferred, molecules can no longer collide; therefore work can no longer occur. This means the end of heat transfer within the universe, thus the end of all life as we know it. The first law of thermodynamics states “During a given process, the net heat transfer minus the network output equals the change in energy” (Oakes, 2016, pg. 506). This tells us that energy can be converted from A to B. This implies that energy is always being transferred with an increase in disorder (entropy), thus achieved with an increase in heat transfer. If energy is always being transferred, then energy cannot be created or destroyed. Therefore, energy will always exist but without heat-transfer, energy can no longer be transferred from one body to another as described in the zero-th law. For example, let’s say we had an insulated system comprising two bodies. Assume the insulation is thick enough to not allow heat transfer inside and outside of the system. During this example, we will neglect radiation. Then let’s say body (A) has a temperature of zero degrees Celsius. This body then comes in contact with another body (B) that has a temperature of twenty degrees Celsius within the isolated system. In this case, the mechanism of heat transfer would be conduction (two bodies coming in contact with each other), and the heat will transfer from B to A until they reach a thermodynamic equilibrium of ten degrees Celsius. Since the system is being isolated by insulation, it would be an adiabatic process (Oakes, 2016, pg. 506). Let’s now consider the second law of thermodynamics which states “During a process, the net entropy of the universe cannot decrease” (Oakes, 2016, pg. 506). To deduce the meaning of the law, let’s consider the two insulated bodies discussed previously except this time the bodies will not come into contact with each other and radiation occurs. Before body (B) is placed into the closed system, which contained a body (A), the temperature of the system stays at a constant of zero degrees Celsius. This also means that the entropy is relative to this temperature and is also constant. When the entropy is constant, we refer to it as an isentropic process (Oakes, 2016, pg. 506). Once body (B) which has a temperature of twenty degrees Celsius is placed within the closed system, then radiation will transfer body (B)'s heat throughout the system. When this process occurs the entropy of the system can only increase because the heat is being distributed throughout the system. Eventually, the system will reach a state of thermodynamic equilibrium of ten degrees Celsius, but before reaching this state the process of heat transfer must occur. During the process, the entropy can only increase until the system reaches a thermodynamic equilibrium at which point (A) and (B) will be ten degrees Celsius. Therefore, the process of heat transfer can only increase entropy until the process reaches a thermodynamic equilibrium.
This is my first time dealing with thermodynamics so please excuse my ignorance. I appreciate all forms of constructive criticism. Also, I know that I have not covered all the points required by the assignment. I wanted to ensure this part is correct before completing the rest.
Thank you,
I have to write a paper about entropy and how it relates to the laws of thermodynamics, energy, and work. I have taken a deductive approach starting from the zero-th law to the second law of thermodynamics as follows.
Entropy is the disorder of a system (Class Video, 2019). To describe entropy, let’s begin by discussing what a system is. A system can be described as any mass which consists of molecules. A room, moon, planet, sun, galaxy, and the universe are all systems. They all comprise molecules but what drives these molecules to become disordered? Well, let’s think of boiling water, the system would be the pot that boils the water. As the water increases in temperature, the molecules begin to collide at a much faster rate, which implies an increase in entropy. When one closes their eyes and imagines millions of molecules colliding with one another, would they refer to this state as ordered or disordered? It would be disordered. For the molecules to be in order, they would need to halt their motion. Therefore, a state of order would be when molecules are no longer in motion, and a state of disorder is when the molecules are in motion. Then it also goes to say, that when heat is transferred, there is a disorder in a system and when the heat is not being transferred, there is order in a system. This means energy will always exist in the universe, but energy requires heat to be transferred from one body to another. Therefore, without heat being transferred in a system work cannot occur. Now that we have established what entropy is let’s continue by deducing how it relates to the laws of thermodynamics. We will begin with the zero-th law of thermodynamics which states “if two bodies are equal in temperature to a third, they are equal in temperature to each other” (Oakes, 2016, pg. 506). When one thinks of how the universe transfers heat, they will think of stars and radiation. Then how does the zero-th law and entropy relate to one another? When the universe reaches absolute zero, the zero-th law applies. If there is heat being transferred in the universe, then there will be disorder. If heat is no longer being transferred in the universe, then the universe will reach a state of order. All life will cease, to exist since all bodies within the universe will be equal in temperature, of absolute zero. This implies no heat is being transferred in the universe thus reaching a thermodynamic equilibrium. A thermodynamic equilibrium occurs “when the properties do not vary from point to point in a system and there is no tendency for change”. Following the definition, we can conclude that this is an isothermal process. This means that the surface temperature is constant, the ambient temperatures are constant. Therefore, all temperatures are equal to absolute zero. This implies the energy being transferred during thermodynamic equilibrium should equal zero, when heat is no longer being transferred, molecules can no longer collide; therefore work can no longer occur. This means the end of heat transfer within the universe, thus the end of all life as we know it. The first law of thermodynamics states “During a given process, the net heat transfer minus the network output equals the change in energy” (Oakes, 2016, pg. 506). This tells us that energy can be converted from A to B. This implies that energy is always being transferred with an increase in disorder (entropy), thus achieved with an increase in heat transfer. If energy is always being transferred, then energy cannot be created or destroyed. Therefore, energy will always exist but without heat-transfer, energy can no longer be transferred from one body to another as described in the zero-th law. For example, let’s say we had an insulated system comprising two bodies. Assume the insulation is thick enough to not allow heat transfer inside and outside of the system. During this example, we will neglect radiation. Then let’s say body (A) has a temperature of zero degrees Celsius. This body then comes in contact with another body (B) that has a temperature of twenty degrees Celsius within the isolated system. In this case, the mechanism of heat transfer would be conduction (two bodies coming in contact with each other), and the heat will transfer from B to A until they reach a thermodynamic equilibrium of ten degrees Celsius. Since the system is being isolated by insulation, it would be an adiabatic process (Oakes, 2016, pg. 506). Let’s now consider the second law of thermodynamics which states “During a process, the net entropy of the universe cannot decrease” (Oakes, 2016, pg. 506). To deduce the meaning of the law, let’s consider the two insulated bodies discussed previously except this time the bodies will not come into contact with each other and radiation occurs. Before body (B) is placed into the closed system, which contained a body (A), the temperature of the system stays at a constant of zero degrees Celsius. This also means that the entropy is relative to this temperature and is also constant. When the entropy is constant, we refer to it as an isentropic process (Oakes, 2016, pg. 506). Once body (B) which has a temperature of twenty degrees Celsius is placed within the closed system, then radiation will transfer body (B)'s heat throughout the system. When this process occurs the entropy of the system can only increase because the heat is being distributed throughout the system. Eventually, the system will reach a state of thermodynamic equilibrium of ten degrees Celsius, but before reaching this state the process of heat transfer must occur. During the process, the entropy can only increase until the system reaches a thermodynamic equilibrium at which point (A) and (B) will be ten degrees Celsius. Therefore, the process of heat transfer can only increase entropy until the process reaches a thermodynamic equilibrium.
This is my first time dealing with thermodynamics so please excuse my ignorance. I appreciate all forms of constructive criticism. Also, I know that I have not covered all the points required by the assignment. I wanted to ensure this part is correct before completing the rest.
Thank you,