studiot

If you wish to create a new system of thermodynamics based on your own private definitions, you will find it very hard in this world. Better to learn and use the established ones.

Well I assume you have the equation for the efficiency, which does indeed show that [math]e = 1 - \frac{1}{{{r^{y - 1}}}}[/math] Since the compression ration, r is greater than 1. In the derivation of this equation use is made of the fact that the compressions are isentropic (adiabatic) so that the expressions [math]\frac{{{T_2}}}{{{T_1}}} = \frac{{{T_3}}}{{{T_4}}} = {r^{y - 1}}[/math] hold good. These are used along with the basic definition for efficiency (output/input) to derive the above expression. So the short answer to your question is becasue the two compressions are isentropic (adiabatic).

Before you can identify your input energy, you must specify your system, system boundary and system process. Input energy is defined as energy that crosses the system boundary during the system process. So if your system is the barrel of fuel, than no, the chemical energy stored in the fuel is not input energy it is internal energy.

Did you read the referenced article? If so how do you reconcile the solution to the differential equation (where the exponential comes in) with your theory?

This is a claim but I see no maths to substantiate it. This seems a fairly easy to follow derivation of radioactivity probability. http://www.csupomona.edu/~pbsiegel/bio431/texnotes/chapter2.pdf

Entropy is the ratio of the quantity of heat transferred across a system boundary to the temperature of transfer.

But what does that have to do with entropy? And focused light still travels at the speed of light.

If it's not a stupid question, how would you move the magnet once you had attached it to the vehicle? Could you not use whatever to pull the car directly?

Defy entropy ? What on earth do you mean? Perhaps you could put some numbers or at least equations to it?

Sometimes we don't want to reduce the eddy currents. Look up the 'eddy brake' or 'eddy brake disk'. Knowing what enhances the effect can point towards reducing it.

If you are talking about algebraic identities Consider the two equations 3x2+8x+6 = 2x2+5x+4 3x2+8x+6 = (x2+4x+1) + (2x2+4x+5) The first is only true for certain values of x - This is an equation. The second is true whatever the value of x - This is an identity. So you need to show that the condition is true for all x.

I do not have access to this book now, but try here Charles Taylor : Ancient and Modern Geometry of Conics (Cambridge 1881) contains much history of the subject. The original book was by John Wallis in about 1661

As I said I was not available over the bank holiday but can carry on now. The problem with air bubbles is that they presumabably lead to a homogenous material. Entrained bubbles will also lower the susceptibility in the flux direction. The point I have been trying to emphasise is that the eddy currents act in a particular direction, so you only want to change the properties in that direction. I also noted that eddy currents are circulatory in nature. The reverse emf they generate depends upon the area of the circle. Again entrained bubbles would not reduce that area in the way that complete separation by lamination provides. Finally in any material where the emf is induced by motion in a steady field, rather than a changing field, the emf is induced in all the moving material immersed in the field. You need some part of the material that is not immersed in the field for the return half of the circulatory current to flow.

I do believe that this relationship was known to the ancientGreeks. Pappus wrote The four books of Euclid's 'Conics' were completed by Appolonius, who added four more and gave us eight books of Conics. However Euclid's books were lost. Aristaeus wrote five further books of the Conics. These books contained all the knowledge to prove geometrically the relationship ie equivalent statements, so perhaps it was never explicity stated, it was used however.

Hello gwyiomi, since this is homework, I was looking for your start on the problem, or at least your thoughts on how to start, but couldn't find them. Hint: Can you rewrite the equation of the line in a more useful manner?

I think we are loosing the point that nobody's theory is perfect (even Einstein's). Every theory is only a model and the wise man knows when to use it and when to look for something better. He does not automatically say "The theory did not work out 'here' so should be discarded for all other purposes, as so many posters do."

Amaton have you seen this thread and my post #7 in particular. http://www.scienceforums.net/topic/78136-what-is-mathematics/ Mathematics was officially plural in the days before America was discovered, and was taught in Latin as a group of disciplines at European universities. In modern times it is now officially singular, but the s is retained.

This would appear to be a homework question. You need to tell us what start you have made with the problem.

Not really. It is impossible to set up a truly 2D coordinate system on the surface of a 3D object. Take for instance a sphere. You can specify where on the surface a point lies, but you cannot tell the distance between two points without at least one measurement in the third dimension. The same is true of any 3d object.

Please explain.

Thank you for the correction on timing, imatfaal. But we do have geometry and we do have dimensions, though some argue about how many; and others worry about the (apparent) granularity of reality. Granularity is a real issue and addresses the difference between a quantised or discrete view of reality and the mathematics of continuity and continuous functions. Professor Shan Majid has written a book about this.

But in general they don't contradict, one or the other ( or even both) is just misapplied. Science is a developing subject. Developing in the light of new facts, observations, information. Here is a short story from the past. In the 1880s and 1890s scientists used the best physics available to calculate the age of the earth. They were able to estimate the temperature of the sun reasonably accurately and also the size of the earth. Using thermodynamic laws of cooling which were well established by then they worked out how long it would take for an earth sized chunk of stellar material to cool to the temperature of the earth. They came up with 4000 years. This caused great controversy at the time. They had no knowledge of any other source of heat for the earth so they applied perfectly good theory inappropriately and came up with a wildly inaccurate answer. We know today that radioactivity has kept the earth's temperature as it is for around a million times as long. As regards classical v quantum mechanics. Do not make the same mistake trying to consider applying classical mechanics to 'particles' that obey the same laws as billiard balls. Quantum mechanics is our best model to date of how they actually operate, but it is incomplete and will one day be replaced by better in areas where it has difficulty.

We see thread after thread complaining that; Relativity is wrong QM is wrong Newton is (was) wrong Aunt Sally's cake recipe is wrong. etc There is no perfect theory. Usually because they are incomplete. But that does not mean they are not useful, so long as we understand the limitations and stay within them. As a for instance Take a theodolite and measure the vertical angle to a remote point up is positive, down is negative) and you can calculate the vertical height of one above the other by trigonometry. right? Sometimes, but I have seen situations where a positive vertical angle has been recorded in both directions. This effect can never be resolved by trigonometry, it needs new theory.

You do not need to apologise for your English. It is plenty good enough. It is your thinking I am having trouble following. What do you mean by "information" and "interaction". If you are going to complain base your argument on exactitude you need to offer exactly precise definitions

Consider what is meant by your statement "Know the path" That implies either an absolute coordinate system that we know does not exist or that you can breach the uncertainty principle to specify any path that accurately.