There are reversible and irreversible processes. Just as the names suggests,one can be reversed and the other can't.
But why did it tell you that now? Checking your vocabulary? Nop!
I need to make a statement that, "All the natural processes I the universe is irreversible. It can't be undone"
Burning a wooden piece, making some food, digestion, weaving some clothe,electricity,giving birth,growing,dying and almost all the natural processes are irreversible. We can also say,almost all the reversible processes are ideal in nature or it isn't a real one. We just use it to study. Just study.
------------------
From the studies of efficiency of an engine, scientists and engineers have found that, An engine is also a thing which does an irreversible process.
Efficiency,as the word suggests is the quality or capability of something to do something efficient. 😃
For an engine,it defines how perfect it can work. There is ideal engine and real engine. Ideal engine exists only in text books for the purpose of studying as it is ideal one and real engines exists in reality. However ideal engine (which exists only in books,which are said to be the perfect role models :P ) is the more efficient than a real engine. It is like, a 1 Litre bottle can never measure 1Litre,as there will always be a manufacturing error might be ranging from microscopic level to nanoscopic or even picoscopic or so on.
The equation which describes efficiency of an engine is [ 1- Q'/Q ]
For the ideal case it can also be derived as [ 1- T'/T], where Q is representing the heat and T of course the temperature. Only for the ideal case,we can derive the equation with T from that of Q. (which means, equation of Q is the general one for all)
So [1-Q'/Q] is always less than [1-T'/T] or to be more specific, by rearranging we will get, [ Q'/T' - Q/T = 0 ]
The value of this difference always a positive one. Why? For every process we takes some energy,use some and leaves the remaining. The difference between taken energy and leftover energy will be positive right? Because that is the one which we used to does the work!
This clearly states that, the second term Q/T is smaller. For an engine,heat only flows from higher to lower temperature. Hence T<T'
For every natural processes this leftover energy,is dumping onto our surroundings,globally to the nature or.... Universally to the universe.
Hence for every natural processes little little such energies will gets dumped. [ratio of 'change in Q' to T is the relation for entropy]. As the T<T' and Q/T is entropy... Lower denominator produces higher entropy (for the same Q) or entropy is positive for every natural processes. Which means entropy is being increased always, from burning of a wooden price to burning of a star,which again means the entropy of universe is always increasing.
But what does this really mean? What does it have to do with us? Do it bothers me? Why should I care?
But why did it tell you that now? Checking your vocabulary? Nop!
I need to make a statement that, "All the natural processes I the universe is irreversible. It can't be undone"
Burning a wooden piece, making some food, digestion, weaving some clothe,electricity,giving birth,growing,dying and almost all the natural processes are irreversible. We can also say,almost all the reversible processes are ideal in nature or it isn't a real one. We just use it to study. Just study.
------------------
From the studies of efficiency of an engine, scientists and engineers have found that, An engine is also a thing which does an irreversible process.
Efficiency,as the word suggests is the quality or capability of something to do something efficient. 😃
For an engine,it defines how perfect it can work. There is ideal engine and real engine. Ideal engine exists only in text books for the purpose of studying as it is ideal one and real engines exists in reality. However ideal engine (which exists only in books,which are said to be the perfect role models :P ) is the more efficient than a real engine. It is like, a 1 Litre bottle can never measure 1Litre,as there will always be a manufacturing error might be ranging from microscopic level to nanoscopic or even picoscopic or so on.
The equation which describes efficiency of an engine is [ 1- Q'/Q ]
For the ideal case it can also be derived as [ 1- T'/T], where Q is representing the heat and T of course the temperature. Only for the ideal case,we can derive the equation with T from that of Q. (which means, equation of Q is the general one for all)
So [1-Q'/Q] is always less than [1-T'/T] or to be more specific, by rearranging we will get, [ Q'/T' - Q/T = 0 ]
The value of this difference always a positive one. Why? For every process we takes some energy,use some and leaves the remaining. The difference between taken energy and leftover energy will be positive right? Because that is the one which we used to does the work!
This clearly states that, the second term Q/T is smaller. For an engine,heat only flows from higher to lower temperature. Hence T<T'
For every natural processes this leftover energy,is dumping onto our surroundings,globally to the nature or.... Universally to the universe.
Hence for every natural processes little little such energies will gets dumped. [ratio of 'change in Q' to T is the relation for entropy]. As the T<T' and Q/T is entropy... Lower denominator produces higher entropy (for the same Q) or entropy is positive for every natural processes. Which means entropy is being increased always, from burning of a wooden price to burning of a star,which again means the entropy of universe is always increasing.
But what does this really mean? What does it have to do with us? Do it bothers me? Why should I care?
No comments:
Post a Comment