5 min read•december 31, 2022
Krish Gupta
Daniella Garcia-Loos
Krish Gupta
Daniella Garcia-Loos
In this section, we finally get to the . This section is heavy on theory and understanding of math rather than its application. This section might be one of the hardest to understand because it deals with intangible quantities, so just try your best🔥
is disorder. That is the most surface level definition ever. Some people also define as molecular freedom. You can also define as randomness or lack of predictability. Also the universe favors . The universe wants more disorder👓
The states that the of the system and its surroundings will never decrease. So the or disorderness can either stay the same or increase.
Calculating is not tested on the exam but we will learn briefly about it anyways in case you study it in college. at a point is the ratio between heat and temperature and is represented by the letter S. S=Q/T
There are two types of thermodynamic processes we can think about based on .
Reversible - these processes can be done forward or backwards. These processes do not increase the of the universe: stays constant. A famous example of this is the . Carnot cycles are the most efficient. They consist of 2 adiabatic processes and 2 isothermal processes. The gas is returned to its original state and no increase in occurs.
Irreversible - these processes can only be done in one direction. The of the universe does increase due to irreversible processes. All real life engines perform irreversible processes. and are some of the most common examples.
In thermodynamics, the tendency of an isolated system to move toward a state of higher disorder is known as the "arrow of time."
These topics are not quite tested on the AP exam anymore but used to show up on the exam several years ago and are taught in several college courses so we will quickly go over them.
- heat is imputed from a high temperature then some is converted to work and the rest in released as low temperature 🔥
/ - work is done in conjunction with low temperature to kick out higher temperature heat 🧊
Here are some key points about :
Here are some key points about and :
Example Problem:
Explain how the second law of thermodynamics is related to the state function called and how behaves in reversible and irreversible processes. In your explanation, provide an example of a process that is reversible and another that is irreversible, and explain how the changes in each case.
To answer this question, you could describe the second law of thermodynamics, which states that the total of a closed system will always increase over time. Define as a measure of the disorder or randomness of a system, and explain how it is a state function, meaning that it depends only on the state of the system and not on the path taken to reach that state.
An example of a reversible process, such as a gas expanding and contracting in a cylinder, and explain how the changes in a reversible process. Give an example of an irreversible process, such as a gas expanding into a vacuum, and explain how the changes in an irreversible process. Explain how the increase in in irreversible processes is what drives the arrow of time and why the past and future are fundamentally different.
2nd Law of Thermodynamics
: The 2nd Law of Thermodynamics states that in any natural process, the total entropy of a closed system always increases or remains constant. It implies that energy tends to disperse and systems tend to move towards a state of greater disorder.Carnot Cycle
: The Carnot Cycle is a theoretical thermodynamic cycle that consists of four reversible processes: two isothermal processes and two adiabatic processes. It is used as a benchmark for the maximum efficiency that any heat engine can achieve.Entropy
: Entropy is a thermodynamic property that measures the degree of disorder or randomness in a system. It quantifies how spread out or dispersed the energy and particles are within a system.Heat Engines
: Heat engines are devices that convert thermal energy into mechanical work, typically by allowing heat to flow from a high-temperature region to a low-temperature region.Heat Pumps
: Heat pumps are devices that transfer heat from a colder area to a warmer area, using mechanical energy. They can be used for both heating and cooling purposes.Refrigerators
: Refrigerators are appliances that remove heat from their interior compartments and release it into their surroundings, resulting in lower temperatures inside.5 min read•december 31, 2022
Krish Gupta
Daniella Garcia-Loos
Krish Gupta
Daniella Garcia-Loos
In this section, we finally get to the . This section is heavy on theory and understanding of math rather than its application. This section might be one of the hardest to understand because it deals with intangible quantities, so just try your best🔥
is disorder. That is the most surface level definition ever. Some people also define as molecular freedom. You can also define as randomness or lack of predictability. Also the universe favors . The universe wants more disorder👓
The states that the of the system and its surroundings will never decrease. So the or disorderness can either stay the same or increase.
Calculating is not tested on the exam but we will learn briefly about it anyways in case you study it in college. at a point is the ratio between heat and temperature and is represented by the letter S. S=Q/T
There are two types of thermodynamic processes we can think about based on .
Reversible - these processes can be done forward or backwards. These processes do not increase the of the universe: stays constant. A famous example of this is the . Carnot cycles are the most efficient. They consist of 2 adiabatic processes and 2 isothermal processes. The gas is returned to its original state and no increase in occurs.
Irreversible - these processes can only be done in one direction. The of the universe does increase due to irreversible processes. All real life engines perform irreversible processes. and are some of the most common examples.
In thermodynamics, the tendency of an isolated system to move toward a state of higher disorder is known as the "arrow of time."
These topics are not quite tested on the AP exam anymore but used to show up on the exam several years ago and are taught in several college courses so we will quickly go over them.
- heat is imputed from a high temperature then some is converted to work and the rest in released as low temperature 🔥
/ - work is done in conjunction with low temperature to kick out higher temperature heat 🧊
Here are some key points about :
Here are some key points about and :
Example Problem:
Explain how the second law of thermodynamics is related to the state function called and how behaves in reversible and irreversible processes. In your explanation, provide an example of a process that is reversible and another that is irreversible, and explain how the changes in each case.
To answer this question, you could describe the second law of thermodynamics, which states that the total of a closed system will always increase over time. Define as a measure of the disorder or randomness of a system, and explain how it is a state function, meaning that it depends only on the state of the system and not on the path taken to reach that state.
An example of a reversible process, such as a gas expanding and contracting in a cylinder, and explain how the changes in a reversible process. Give an example of an irreversible process, such as a gas expanding into a vacuum, and explain how the changes in an irreversible process. Explain how the increase in in irreversible processes is what drives the arrow of time and why the past and future are fundamentally different.
2nd Law of Thermodynamics
: The 2nd Law of Thermodynamics states that in any natural process, the total entropy of a closed system always increases or remains constant. It implies that energy tends to disperse and systems tend to move towards a state of greater disorder.Carnot Cycle
: The Carnot Cycle is a theoretical thermodynamic cycle that consists of four reversible processes: two isothermal processes and two adiabatic processes. It is used as a benchmark for the maximum efficiency that any heat engine can achieve.Entropy
: Entropy is a thermodynamic property that measures the degree of disorder or randomness in a system. It quantifies how spread out or dispersed the energy and particles are within a system.Heat Engines
: Heat engines are devices that convert thermal energy into mechanical work, typically by allowing heat to flow from a high-temperature region to a low-temperature region.Heat Pumps
: Heat pumps are devices that transfer heat from a colder area to a warmer area, using mechanical energy. They can be used for both heating and cooling purposes.Refrigerators
: Refrigerators are appliances that remove heat from their interior compartments and release it into their surroundings, resulting in lower temperatures inside.© 2024 Fiveable Inc. All rights reserved.
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