Explain Entropy & Heat Flow: Thermodynamic Formulas & Multiplicity

In summary: However, in summary, according to the conversation, the bigger the entropy of a system, the more heat energy can enter it from the surroundings. This can be explained through the thermodynamic formulas, such as the thermodynamic identity, and in terms of multiplicity. The helmholtz energy, which is the total energy needed to create a system, can be expressed as TS, where S is the final entropy of the system. This suggests that the more entropy a system has, the more energy it can absorb as heat from the surroundings.
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aaaa202
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In my book it says: The bigger entropy of a system, the more heat from the surroundings can enter it. Now, I don't really understand why that is completely. Can anyone explain me? - both in terms of the actual thermodynamic formulas (thermodynamic identity etc.) and in terms of multiplicity?

Maybe I have misunderstood something so here is what my book says in exact words:
"The helmholtz energy F is the total energy needed to create a system minus the energy you can get for free from an atmosphere at temperature T. This energy is given by TS, where S is the final entropy of the system. THE MORE ENTROPY A SYSTEM HAS THE MORE OF ITS ENERGY CAN ENTER AS HEAT "
 
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  • #2
aaaa202 said:
In my book it says: The bigger entropy of a system, the more heat from the surroundings can enter it. Now, I don't really understand why that is completely. Can anyone explain me? - both in terms of the actual thermodynamic formulas (thermodynamic identity etc.) and in terms of multiplicity?

Maybe I have misunderstood something so here is what my book says in exact words:
"The helmholtz energy F is the total energy needed to create a system minus the energy you can get for free from an atmosphere at temperature T. This energy is given by TS, where S is the final entropy of the system. THE MORE ENTROPY A SYSTEM HAS THE MORE OF ITS ENERGY CAN ENTER AS HEAT "
As a Physics Forums mentor with expertise in Thermodynamics, I have no idea what this means.
 

FAQ: Explain Entropy & Heat Flow: Thermodynamic Formulas & Multiplicity

1. What is entropy and how is it related to heat flow?

Entropy is a measure of the disorder or randomness in a system. It is related to heat flow through the second law of thermodynamics, which states that the total entropy of a closed system will never decrease over time. This means that heat will always flow from hot objects to cold objects, increasing the overall entropy of the system.

2. Can you explain the thermodynamic formula for entropy?

The thermodynamic formula for entropy is S = kB * ln(W), where S is the entropy, kB is the Boltzmann constant, and W is the number of microstates that a system can occupy. This formula relates the macroscopic concept of entropy to the microscopic concept of multiplicity, which is the number of ways a system can be arranged at the microscopic level.

3. How does entropy affect the direction of heat flow?

Entropy affects the direction of heat flow through the second law of thermodynamics, which states that heat will always flow from hot objects to cold objects, increasing the overall entropy of the system. This means that in a closed system, heat will spontaneously flow from a hot object to a cold object, as this will increase the overall disorder of the system.

4. How does multiplicity affect the overall entropy of a system?

Multiplicity is the number of ways a system can be arranged at the microscopic level, and it is directly related to the overall entropy of a system. As the number of microstates increases, so does the multiplicity and therefore the entropy. This means that a more disordered system with a higher number of microstates will have a higher entropy than a more ordered system with a lower number of microstates.

5. Can you give an example of how entropy and heat flow are related in real life?

An example of how entropy and heat flow are related in real life is the melting of ice cubes in a glass of water. The ice cubes, which have a lower temperature, will transfer heat to the water, which has a higher temperature. As the ice cubes melt, the overall entropy of the system increases, as the water molecules become more disordered. This process will continue until the temperature of the water and ice cubes equalize, and the system reaches thermal equilibrium.

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