DOES ANYONE KNOW WHAT IS THE 2ND LAW OF THERMODYNAMICS?
2nd LAW OF THERMODYNAMICS
i believe that it is, The final form that energy takes is heat.
Not positive but pretty sure
because i know the first is that energy and not be created or destroyed.
Not positive but pretty sure
because i know the first is that energy and not be created or destroyed.
Isn't it "The total entropy of a closed system can not decrease"?
| DoctorBeaver wrote: |
| Isn't it "The total entropy of a closed system can not decrease"? |
Close, it is "the total entropy of any thermodynamically isolated system tends to increase over time, approaching a maximum value.", i.e. energy splits equally between all states and the system approaches thermal equilibrium.
It is the reason why heat energy travels to cold areas, why high pressure tends to flow towards low pressure. It states that these actions are irreversible. It describes how the universe is expanding and that given it's conditions at the moment it will not go back into a big crunch.
Entropy describes the balance between its current state and an alternative state. If there is an uneven balance between the two, the action is driven towards the more balanced state.
If the entropy for both "before" and "after" are the same, then the event is reversible. Some chemical reactions are reversible.
Entropy describes the balance between its current state and an alternative state. If there is an uneven balance between the two, the action is driven towards the more balanced state.
If the entropy for both "before" and "after" are the same, then the event is reversible. Some chemical reactions are reversible.
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| Close, it is "the total entropy of any thermodynamically isolated system tends to increase over time, approaching a maximum value.", i.e. energy splits equally between all states and the system approaches thermal equilibrium. |
That's what I meant
| Lennon wrote: |
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Entropy describes the balance between its current state and an alternative state. If there is an uneven balance between the two, the action is driven towards the more balanced state. |
this sentence does not mean anything. please disregard it.
The second law of thermodynamics states that a system must have an entropy change for any un-ideal process. In other words if you add energy to a system its "chaos" will increase. This leads to the Clausius statement and the Kelvin-Planck statement which makes the second law useful. They say that heat must transfer from a hot source to a cold source and that a device working on a cycle must have two reservoirs a hot and a cold.
There are two definitions each pertaining to PHYSICS and CHEMISTRY:
PHYSICS:
CHEMISTRY:
PHYSICS:
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In simple terms it says that the efficiency of a heat engine can never reach unity |
CHEMISTRY:
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The entropy of all spontaneous processes in the universe increases The free energy of all spontaneous processes in the universe decreases |
there are a few different statements:
It also states that efficiency of a heat engine can never be 100% and also defines the efficiency of a heat engine
It also states that efficiency of a heat engine can never be 100% and also defines the efficiency of a heat engine
| yrazvi wrote: |
| DOES ANYONE KNOW WHAT IS THE 2ND LAW OF THERMODYNAMICS? |
In scientific language.. the entropy of an isolated system is always increasing. I understand it this way. The system will be found after sufficiently long time interval in the state with the highest probability. This state is the equilibrium state. For detailed inforamtion see Landau
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