Is work path dependent or independent?
The work a conservative force does on an object is path-independent; the actual path taken by the object makes no difference.
Why heat is a path dependent function?
Two important examples of a path function are heat and work. These two functions are dependent on how the thermodynamic system changes from the initial state to final state. These two functions are introduced by the equation ΔU which represents the change in the internal energy of a system.
Does work depend on path in thermodynamics?
Work done in path dependent. There are infinitely many paths that can be taken to move the system from state A to state B and each path will give a different value of work done. The work done in path A-B is greater than the work done in path A-C-B. (Work done is give by the area under the PV curve and V axis).
Is entropy path dependent?
The entropy is a state variable, so the entropy change should not dependent on the path between the initial and final state. If a process occurs in a closed system, the entropy of the system increases for irreversible processes and remains constant for reversible processes.
Is entropy a path function?
Since entropy is a state function, the entropy change of the system for an irreversible path is the same as for a reversible path between the same two states. In classical thermodynamics, the entropy of a system is defined only if it is in thermodynamic equilibrium.
Is entropy generation a path function?
Answer. Answer: Entropy is point function. It is a point function.As by Clausius inequality for a reversible cycle,dq/t =0 which means this quantity must represent a change in a property(hence a point function) which is entropy.
What causes entropy generation?
Entropy production (or generation) is the amount of entropy which is produced in any irreversible processes such as heat and mass transfer processes including motion of bodies, heat exchange, fluid flow, substances expanding or mixing, anelastic deformation of solids, and any irreversible thermodynamic cycle, including …
What do you mean by entropy generation?
The entropy generation is a measure of the magnitudes of the irreversibilities present during the process. Entropy Balance. Entropy is a measure of molecular disorder or randomness of a system, and the second law states that entropy can be created but it cannot be destroyed.
How can entropy generation be reduced?
Furthermore, for a fixed value of “a” the entropy decreases as the needle velocity decreases or the free stream velocity increases, so by increasing the free stream velocity or by decreasing the velocity of the thin needle one can minimize the entropy generation, which is the main goal of the second law analysis, the …
Is entropy change always positive?
In an irreversible process, entropy always increases, so the change in entropy is positive. The total entropy of the universe is continually increasing. There is a strong connection between probability and entropy. This applies to thermodynamic systems like a gas in a box as well as to tossing coins.
Can a reaction be spontaneous if the entropy is negative?
If a reaction is exothermic ( H is negative) and the entropy S is positive (more disorder), the free energy change is always negative and the reaction is always spontaneous….
| Enthalpy | Entropy | Free energy |
|---|---|---|
| endothermic, H > 0 | decreased disorder, S < 0 | reaction is never spontaneous, G > 0 |
What is the formula for entropy change?
Entropy changes (ΔS) are estimated through relation ΔG=ΔH−TΔS for finite variations at constant T.
What happens when entropy reaches maximum?
The ‘heat-death’ of the universe is when the universe has reached a state of maximum entropy. This happens when all available energy (such as from a hot source) has moved to places of less energy (such as a colder source). Once this has happened, no more work can be extracted from the universe.
Will all energy eventually become useless?
We always lose. The electricity made by our little turbine isn’t enough to keep the system going. It will eventually “wind down” and stop, because all of the energy will eventually become low-grade and useless.
What is the maximum entropy of the universe?
Irreversible processes in the universe can only happen if there is an entropy gap Δ between the entropy of the observable universe Suni and its maximum entropy Smax: Δ = Smax − Suni.
How far away is the heat death of the universe?
This is the timeline of the Universe from Big Bang to Heat Death scenario. The different eras of the universe are shown. The heat death will occur in 10100 years, if protons decay.