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studiot

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Everything posted by studiot

  1. Your question states What is infinity to the power 0? Before you can discuss this question you need to present which rules you are invoking concerning multiplication / exponentiation and show that that infinity is one of those mathematical objects that obeys these rules.
  2. Melting means breaking the bonds that hold the solid together. To do this you have to put energy in. The bonds that hold foreign atoms in the solid matrix (impurities) are in general weaker than the bonds to the 'proper' atoms. Thus requiring less energy to break.
  3. I have to say I'm with MigL. Mig did say control their spending, which does not mean there is no good spending. Consider this version of the 'Ancient Mariner' 'And he puncheth one in three' Just because he smiled sweetly at 2/3 of the passers by does it mean he can control his punching?
  4. Enough talk. Sorry Mike, but here is some maths. Sorry also that my artwork is not up to your standards, you will just have to use your imagination there. Consider a weight hanging by a string from the frustrum of a witch's hat cone. The weight rests on the side of the cone. Ignoring friction, the weight is supported against gravity by the tension in the string and the reaction with the surface of the cone. Now the weight is swung so it is set in motion travelling around the surface, but not leaving it. The weight therefore travels in a horizontal circle around the cone. In the attached sketch I have shown two possible methods of analysis. On the left is a dynamic analysis by Newton's laws using only the real forces that are acting. On the right is the D'Alembert transformation to a static equilibrium analysis by the introduction of a fictious centrifugal force. Both analyses arrive at the same results and therefore look pretty similar.
  5. I did tell you how to solve the maths, and therefore that it is solvable. Unfortunately I don't have acess to my usual latex editor so I did my best to present it in a standard way.
  6. So why doesn't 'your friend' join and ask his own questions?
  7. Was that report linked by Sensei the best the US government could do? I really can't see that it showed enough to conclude much of anything. It is, however, well enough known that thick timber will hold its strength longer than equivalent structural steel in a fire, for UK building codes to require fire protection to supporting structural steel members. Roof members are largely unprotected or lightly protected. But that report tested such a tiny amount of steel for which it can't even identify the source that the conclusions are IMHO largely meaningless. I have investigated steel motorway bridge beams following intense fires from road fuel tankers and did a more thorough job than that.
  8. I can't afford to get on a UK train, let alone travel on one. Not that it would be possible anyway. More government nonsense, both West Coast Main lines were closed over Easter. I am currently doing some stuff in Dundee and, when the time comes to return the 500 miles home, it will actually be cheaper to hire a car for the day, include the return charge and petrol, than to buy a train ticket back.
  9. This question really belongs in the province of physical chemistry. A gel is an example of a disperse system, the old name for which was a colloid. A disperse system consists of two materials intimately mixed so they don't separate in normal conditions and act as if they were one substance. The two materials are called the disperse medium (which corresponds to the solvent in a solution) and the disperse phase (which corresponds to the solute in a solution) The mention of phase brings up that the two substances may be in different states, So smoke is a solid dispersed in a gas and foam is a gas dispersed in a liquid. Gels are harder to characterize. They are a mixture of a liquid and a solid, but which is the disperse medium and which the phase is sometimes hard to tell, though their softness and flowability would suggest a solid in a liquid most of the time.
  10. To him that hath, even more shall be given And from him that hath not, yet more shall be taken. But don't worry, Mig. The waste race is one the UK will be proud to beat the US in. Half a trillion dollars on a toy train set and a toy boat set of use to no one.
  11. Questionist, You have cIaimed to want to discuss in words not mathematics but I to came to the conclusion you were not interested in serious discussion of any description when you presented a mealy mouthed response to my offer to discuss relativity in words rather than mathematics in the other current relativity thread.
  12. Nor could I. Incomplete would be a better word. I am simply trying to widen horizons, not just necessarily yours.
  13. Hi, pavel. A good example to illustrate exactly what I mean. Let us take Archimedes' Principle. This is a single idea and it leads to the 'Theory of Floating Bodies' which is much broader in scope. Other examples might be the famous treatise 'The Theory of Sound', which embodies many Principles. Or The Theory of Flight or, my favourite The Theory of Bending, which embodies, amongst others, the principle that plane sections remain plane, but is an elegant self contained useful logical construct that enables many highly desireable everyday calculations to be made throughout the world. It also demonstrates another important characteristic of a Theory. There is nothing to say a Theory need be unique and exclusive. (some are some are not). But there are are other methods available to make the bending calculations with the same results.
  14. Not convinced. What about a 'Principle' ? There is also the issue of whether the word theory is singular or plural or a collective noun or what. A single idea is presented as a theorem. A theory generally links more than one idea and/or observation. A theory may contain several theorems. Some reserve/use the word Theory to mean a comprehensive exposition or treatise on a particular subject, not just part of it. Then there is the issue of if you allow that Mathematics is part of Science. If so you must also allow the mathematical definitions including lemma = lesser/minor theoreom, hypothesis, proposition, axiom and so forth. Chanting a catechism about a particularly narrow view of the word is for the baying hounds, not the thinking cognoscenti.
  15. I did not see that post, but it is an interesting (and likeable) way of putting it. +1 Does your presentation run to including any form of uncertainty principle? Your exposition above was completely definite.
  16. Have you studied Banach's contraction mapping theorem? http://en.wikipedia.org/wiki/Banach_fixed-point_theorem
  17. One of the things any successful apprentice has to learn is that machinery of any kind, including computers, is completely unforgiving as it follows the immutable laws of physics. No amount of bluster or cat calling will make a poorly serviced motor or ill programmed computer run well.
  18. Are you extracting the Michael? I'm sorry I thought you said your were studying or working in computers. exp is computer language for exponential.
  19. Strong feelings or not I prefer a civil discussion. And discussion is two way. I can't proceed if I don't know what you think about isotropy and homogeneity (do you know the difference?) to start with.
  20. Rest mass = 0 The function y = {exp(x) - 1} starts and zero and becomes asymptototic to infinity without problem.
  21. Questionist, strong language for scientific discussion. The underlying principle behind special relativity (do you know enough to distinguish between Einstein's two relativity theories and also the Newton/ Galileo one?) is that we wish to assert the homogeneity and the isotropy of space or spacetime or whatever we like to call the 'universe'.
  22. Yes I have this problem from a bog standard Toshiba laptop Windows with Windows 7. Try Fox or Chrome.
  23. Thar's a bit abrupt, I was wondering if you realised the implications of that statement. However, according to WolframAlpha yes that is the correct plane. To check, input the determinant as follows matrix {{x,y,z,1},{1,-2,0,1},{1,-2,2,1},{0,3,2,1}}
  24. Is the coefficient of z truly zero?
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