All about Thermodynamics law

Maxwell Demon

2009-06-24T00:45:00.000-07:00

The demon of Maxwell is a thought experiment proposed by James Maxwell in 1867 for violating the second law of thermodynamics.Maxwell was interested in the kinetic theory of gases, where the properties were reduced thermodynamic thereof to the mechanics of a large number of molecules. The heat was then reduced to a particular form of energy in the form of disorderly agitation of the molecules.

Principle of Carnot

2009-06-20T13:06:00.000-07:00

Thermo. You can not create work in a closed cycle with a single heat source. It takes at least two sources at temperatures T1 and T2 to produce power. The theoretical maximum efficiency is independent while temperatures at which heat is exchanged, the principle of Carnot implies the relationship: Q1 / Q1 + Q2 / Q2 <= 0 with equality for the reversible transformation, Q1 (resp. Q2) designating the

Le Chatelier-Braun's Principle of thermodynamic balance

2009-06-20T11:27:00.000-07:00

Chemist Henry Louis Le Chatelier (1850-1936) was the first to notice that different phenomena thermochemistry obeying a principle can be stated as: "If you tend to change the terms thermodynamic (pressure, temperature, concentration) from one system to the balance, it reacts to oppose, in part, to changes that it requires, so as to obtain a new balance. " The German and the Nobel Prize for

The second principle undermined by quantum mechanics?

2009-06-16T12:30:00.000-07:00

Can we violate the second law of thermodynamics? This question nagging for the Multivac computer in the news of Isaac Asimov The last question may have a positive response according researchers at the Weizmann Institute in Israel. It would suffice to bring the magic formulas of quantum mechanics. The second law of thermodynamics is one of the most solid pillars of physics. It is on it that Albert

Residual entropy and validity of the third law of thermodynamics ..

2009-06-16T11:00:00.000-07:00

When you use energy, the rules are well defined. The first and second laws of thermodynamics have been well understood for more than a century, and the third a little more than a century, but the topic is still considered by most to be rather obscure. That is unfortunate, because these two laws are so important, and because almost everyone has a good understanding of the first and second laws,

Second law of thermodynamics and the unsolved debates

2009-06-10T03:46:00.000-07:00

The total change of entropy of a system and its environment is always positive, and tends to zero for the transformation towards reversibility.The thermodynamics is based on two essential principles:the first-principle, which establishes the equivalence of different forms of energy, including heat and work. It is a principle of conservation, it implies that the sum of the energies associated

The basic theoretical concepts of thermodynamics

2009-06-08T00:49:00.000-07:00

Branch of physics and chemistry related to the study of thermal behavior of the body, the study of energy and its transformations (in particular the internal energy). Thermo. Thermodynamics studies the transformations of the systems (sets of body separated by a physical boundary or not) open or closed (depending on whether or not exchange matter with the outside) insulated or not (depending on

Equilibrium thermodynamics, entropy, time

2009-05-20T05:19:00.000-07:00

One might think that our sense of passing time actually comes from increasing entropy is by measuring how unconscious entropy increases around us that we "feel" the passage of time, as events occur over time ... etc. we can see the thermodynamic equilibrium as a state where entropy increases more (assuming our isolated system), ie not undergoing the most over time. Yet we know that this event, a

Dissipation of energy

2009-05-15T02:43:00.000-07:00

Now imagine that the truck that we have considered so far starts to brake. So he finally stopped (so it has more kinetic energy) at the bottom of the slope (so it has more potential energy rather than at this time). And therefore was able to spend the energy it possessed? In fact, it has not disappeared. Simply, it was dissipated by the brakes of the trolley, and it increases their temperature.

The continuous movement of a second species

2009-05-15T02:29:00.000-07:00

It does not create energy from nothing, ok. But see when you shine a light bulb, it heats, heating and light it encounters. That is, in terms of particles that make us, that light the bulb more thrilled our particles. More an object has particles that vibrate, which are agitated, the more it is hot. A hot object, in fact, because its particles are agitated, a lot of energy. And if once the light

Perpetual motion

2009-05-15T02:18:00.000-07:00

The motion was for a very long (and sometimes still is) a sort of Holy Grail of the inventor, as the transmutation of metals was among alchemists. The idea is simple: what if someone invented one day a kind of universal motor, which would alone any moving mechanism, in short, which could supply energy at will? This would certainly be the inventor for eternal glory ... But it seems that the

Is GreenFuel Technologies a Scam

2009-05-15T00:06:00.000-07:00

The question comes up again and again from various people: "Is GreenFuel a scam?" "Are all these photobioreactor companies scams?"This question is inevitable when someone takes advantage of human nature and wickedness to sell something.Was Skype a scam? Was A.O.L. a scam? Both companies sold at the peak of a hype-wave, and did not live up to the expectations of the acquirer. At the same time

Breaking the Law

2009-05-14T11:13:00.000-07:00

How can one not like GreenFuel Technologies? These people say they can convert emissions from power plants into biofuels using algae in proprietary photobioreactors, which has so far resulted in tons of positive press, awards and accolades. And why wouldn’t it? You take CO2-containing pollutants and turn them into valuable, clean-burning fuels, just when we are running out of oil? Could there BE

The heat pump: How Does an Earth-Energy System Work?

2009-05-10T23:18:00.000-07:00

Heat Pump pump heat from one location and return it to another. That's why, that logically, it is called a "heat pump". All heat pumps operate basically on the same principle. This is a circuit of a liquid that "brings the heat: condensation. When forced to evaporate, it takes the heat that surrounds it. You know this principle is that of sweat. You sue because evaporates, the water is cool. Then

Disorder and waste of energy

2009-05-10T23:14:00.000-07:00

The entropy can be interpreted as a measure of disorder, but we will especially see an increase in entropy means a waste of energy. Imagine a trolley at the top of a slope. Imagine that on wheels, we will install a dynamo bicycle, which charge a battery. The dynamo will take the kinetic energy to the trolley when it will set in motion, and therefore the brake. To those, I hope many who have

Thermodynamics: Principles and Applications

2009-05-09T23:22:00.000-07:00

This is the natural continuation of my previous article entitled Thermodynamics: The Fundamentals. I will present the 4 major principles that are posed by the thermodynamics, which led to the understanding, construction and improvement of thermodynamic machines like the steam engine, the gasoline engine, the heat pump or air conditioner . Zero PrincipleIt's called principle zero because it is

Why keep a room is increasing disorder in the universe ...

2009-05-05T23:59:00.000-07:00

The second law of thermodynamics states that disorder a set of objects left to themselves (ie single) or entropy can only increase with time.We will see that it is not contrary to the second principle that sometimes the order increases. We will take a simple example, and yet very relevant. That is what I found best answer to my dad, who once forced me to keep my room ...Finally, keep her room,

Thermodynamics: the basics

2009-05-01T02:46:00.000-07:00

During my second year of studies, I attended a summer school on the physics of low temperatures and there was obviously a reminder of basic thermodynamics. From memory, here is the introductory sentence of our teacher (who is more than true):"The first time we study the thermodynamics, it does nothing. The second time, we think he understood. And the third time, it is sure to have understood

Equilibrium between liquid and vapor

2009-05-01T01:54:00.000-07:00

In general, we find in nature a balance between liquid and vapor (or gas). This means that both are present, and interact. Here's how it thinks it necessary to design liquid water at the bottom, where the molecules are agitated, but they remain prisoners of the whole. Inevitably, from time to time, the molecules escape from the water. They are ejected by shocks. They become gas above the water.

Thermodynamics?

2009-05-01T01:43:00.000-07:00

Yet it is undoubtedly one of the disciplines of physics that includes the better "with your hands." This is more a perspective on the world that a theory in itself. And it is a very rich.Thermodynamics, the world seen through the prism of energy. Energy is the key concept in this regard - though this concept comes, in fact, mechanics, and is also common to electromagnetism, among others: Can we

The main states of matter

2009-04-29T22:05:00.000-07:00

Water, as well as many other materials, if not all, can exist in different states: solid, liquid, and gaseous.In a gas, molecules are far apart from each other. They are very fast (which means that the gas has a high enough temperature, since temperature measures the degree of agitation of molecules). They bump them, but do not stay together. A gas is compressible if you put in a piston is

Heat and Temperature

2009-04-29T21:53:00.000-07:00

Often confused with heat and temperature, see how the two ideas are quite different, although they are closely related, of course.The simplest to understand is the temperature. In an object, whatever it is, molecules, atoms that constitute it are not static. Instead, they move very quickly, but as they are small, we do not see it, of course.This disorderly agitation of the particles of the object

Temperature

2009-04-29T21:41:00.000-07:00

The temperature of a body is the measure of its molecular agitation. It's a function of the proportion of excited atoms and atoms in the ground state of a body. It represents the average energy of a molecule.(We can understand this definition by defining an excited atom as an atom that vibrates much around its average position).The amplitude of oscillations of an atom around its mean position

Origin of the Second Principle

2009-04-27T10:04:00.000-07:00

We will try to understand exactly where is the trend of the universe to evolve into chaos, taking as example a pool of a rather unusual kind: a pool on which the balls ride without being hindered. Once set in motion, they can stop more ... We will now place, as drawn below, a plate in the middle of the pool, which nevertheless leaves space for the balls to move from side to side. It leaves six

History of Thermodynamics

2009-04-18T00:17:00.000-07:00

The history of thermodynamics has always seemed to me to be not only one of the most interesting but one of the most dramatic episodes to be found in the story of the intellectual progress of the human mind. Starting in an investigation of a purely practical problem of engineering economics, it has grown into a body of doctrine of profound philosophical significance, with consequences which

Improve the thermodynamic efficiency of engines

2009-04-16T21:39:00.000-07:00

Thermodynamics is a branch of physics that studies the transformation of heat into work.Heat is the disorderly movement of the molecules of a body.For labor, we must give meaning to the movement by forcing the molecules to move in one direction with a machine. So give the order to matter.That is when the invention of the steam engine that the nature of the Heat, Labor and the temperature have