studiot

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Everything posted by studiot

  1. studiot

    An ohmic contact

    Very quickly this morning, Some things to realise about what is shown in common textbooks. Textbooks tend to consider the 'equilibrium' contact and how it is achieved, usually using energy diagrams. This is the position in figures 1 to 4 in your link. But there will be zero current flowing in this situation, because there is no complete circuit established. Your link is good because it has a figure 5 which is not an energy level diagram but a voltage / current plot whic shows a complete circuit as well as ohmic (5b) and Schottky action (5a). Working out how the current is carried in a complete circuit will help you a lot. Especially as there is a big difference between P type and N type semiconductors. I don't have time to draw any diagrams until later.
  2. studiot

    Mass/energy equivalence question

    Not really forces, no, although they may be present and indirectly contributory. consider a (small) tank containing a hydrogen and oxygen mixture. This has potential energy you can release by igniting the hydrogen, but there are no forces between the particles whilst the tank sits there. Well there's translational energy (often called kinetic energy) vibrational energy rotational energy Heat energy (which is really a mixture of the above three) Then there's nuclear binding energy and some more esoteric types. Sort of but it get very complicated very quicky when you start talking about the tensors in general relativity that contribute to this.
  3. studiot

    An ohmic contact

    Just use the conventional terminology, like everybody else. Then there is no confusion. A Schottky junction is the same as a metal-semiconductor junction. The emphasis is on the word junction the other words distinguish it from a semiconductor junction device. The other alternative is called an ohmic contact and does not include the word junction. Now that we have got that cleared up how about being more specific with your actual question that a link to an 11 page pdf? (Glancing through the document suggests it is worth reading, )
  4. studiot

    Can have achieve nuclear fusion?

    That's a fair question. Presumably your video included some description of a ball of gas being made of molecules flying around inside the ball and constantly bumping into each other? The average speed of the molecules tells us (determines) the temperature of the ball. But like all averages, some molecular speeds will be faster than this average and some will be slower. Molecules that collide head on get slower and molecules that collide sideways can get faster. So molecules are always changing their speed. The faster a molecule is going the more energy it has So the higher the temperature of the ball the higher the average speed. In order to initiate fusion the impact has to involve a threshold or minimum amount of energy. So this means a minimum speed of impact (head on) between two fast molecules. OK so that's how fusion can start, what does that mean for fusion? Well two things. The bigger the ball, the more chance there is of a series of collisions adding up to some fast enough molecules to fuse on collision. Or the higher the temperature of the ball the fewer the number of suitable collisions required to speed up a few molecules to fusion speed. The Sun is a very large ball of gas so it can initiate fusion at a lower temperature than a smaller ball on Earth or elsewhere. So either we make a ball of gas as large as the Sun (impractical) or we work at a higher temperature. Incidentally, the problem with fusion is not reaching the necessary temperatures, that has been done. It is containing the high temperature plasma (the gas become a plasma at high enough temperatures, but that is another story) long enough to keep the fusion process going. It is also interesting that the Sun is largely made of Hydrogen, whiklst the molten sore of the Earth is a mixture of ferrous metals and is, in fact, hotter than the Sun (at least at the surface). But there is no fusion in the Earth's core, because hydrogen is a lot easier to fuse than 'heavier' elements. Does this help.
  5. I know you have ignored the law of conservation of mechanical energy by introducing friction and some other magic force called 'pression' and then failed to account for their energies in your calculations. The hydraulic systems you have drawn cannot act in the way you describe. You need to know enough Mechanics to understand what they will actually do before putting numbers to things.
  6. studiot

    An ohmic contact

    So tell me again why the first sentence in your initial post was not wrong or rephrase it so I can understand what you actually mean please.
  7. This is complete and utter nonsense in that it utterly ignores the laws of Mechanics. I asked a simple question (Hint the sentence ending in a question mark). The Laws of ScienceForums expect you to answer.
  8. studiot

    Einstein in pre-Nazi Germany

    I don't find it at all suprising that prior to the rise of Stark and the 'Aryan Physics' movement, (1933) when many prominent Jewish academics were replaced by non Jews in Germany that pressure groups had existed for a substantial number of years. Such activity has many precedents in history and even today. Some of this is bloodthirsty and some more 'civilised'. For instance The Protestants burned Bruno at the stake. The Catholics threatened and perhaps tortured Galileo The French Revolution executed Lavoisier whilst Fourier flourished. Both the Tsarists and the Soviets condemned scientists to the gulags (sharashka). All of these were carried out by authoritarian regimes in the height of their powers. But that poser but did not come overnight - it took years in the developing. I also said more 'civilised' The US Presidency clears out most of the heads of departments with an outgoing President, to be replaced by those in favour with the incoming, regardless of how good they were in office. I suppose you couldc all this more civilised because heads no longer roll as they used to in ancient civilisations and past european clearouts.
  9. studiot

    If I can imagine it, it is possible!

    Here endeth the lesson for today read by the Cookie Monster.
  10. studiot

    Electrons in orbit in the atom

    Pauli exclusion Principle https://chem.libretexts.org/Bookshelves/Physical_and_Theoretical_Chemistry_Textbook_Maps/Supplemental_Modules_(Physical_and_Theoretical_Chemistry)/Electronic_Structure_of_Atoms_and_Molecules/Electronic_Configurations/Pauli_Exclusion_Principle and also Hund's Rules https://chem.libretexts.org/Bookshelves/Physical_and_Theoretical_Chemistry_Textbook_Maps/Supplemental_Modules_(Physical_and_Theoretical_Chemistry)/Electronic_Structure_of_Atoms_and_Molecules/Electronic_Configurations/Hund's_Rules
  11. studiot

    An ohmic contact

    A Schottky barrier is high resistance in one direction and low resistance in the other. An ohmic contact is low (ish) resistance in both directions. They are not the same. Read your own reference again thoroughly. Right at the beginning, it says the exact opposite of this Either a Sckottky barrier or an ohmic contact. For your further information the Schottky barrier is formed when the metal is bonded directly to a block of intriniscally N or P type material. This effect occurs with different metals for either N or P, but not both. So bonding aluminium to N type gold to P type creates the Schottky barrier. Doing it the other way round does not. Bonding the metal to a part of the block of N or P type material which is heavily doped to be even more N or P type creates an ohmic contact. Whilst you are digesting this and asking further questions, I will read the rest of your reference.
  12. studiot

    Are Kinetic Energy Weapons Possible?

    KE weapons are amongst the oldest ones we have. Fist, lance, spear, arrow, club, quarrel, ram, cannonball, bullet..........................................
  13. You now have a thread with two pages of nonsense and wasted effort. If you put one tenth the effort of making these diagrams into learning some basic mechanics you would be much further forwards. Properly learning this is urgent for anyone who offers the statement "Blackball 1 already have a force of 60N before striking the piston pusher." Do you know what force is and would you be willing to learn if someone told you?
  14. studiot

    Einstein in pre-Nazi Germany

    No one is trolling you. Of course there was a concept of pure vacuum pre 1930. The constant we are talking about was introduced by Coulomb in 1785, although he used different units from modern SI ones, they were definitely not zero.
  15. studiot

    Einstein in pre-Nazi Germany

    My vacuum has nothing whatsoever to do with QM. This is a thread about Einstein, Relativity and Pre Nazi Germany. Relativity is fully compatible with Electrodynamics (or the other way round if you prefer) when the later is suitably written. Eise did point out that this was Einstein's big breakthrough.
  16. studiot

    Einstein in pre-Nazi Germany

    That is just wriggling. The basic definition of the capacitance assumes an ideal vacuum.
  17. I agree this But not this
  18. studiot

    Einstein in pre-Nazi Germany

    Really? Consider the following thought experiment. Since it is a thought experiment I have the luxury of perfect (i prefer the term ideal) components. I have two perfectly conductive metal parallel plates, each of area 1 sq cm, supported in an ideal vacuum exacltly 1cm apart. They are connected, via ideal short wires, to an ideal 1V battery. Please explain mathematically (Eise did not do this) what the capacitance of this arrangement is, if as you maintain, epsilon nought is zero.
  19. studiot

    Einstein in pre-Nazi Germany

    This is an even more difficult position to defend than your last version. Especially without evidence. preferably of a mathematical nature.
  20. studiot

    Electrons in orbit in the atom

    I think I have heard that if there is an energetic input into an atom then a constituent electron (or electrons?) will may be able to move to a higher energetic level in the atom. The process of moving to a greater energy is called excitation. Excitation does not involve dematerialisation and subsequent rematerialisation. Note I said greater energy not a higher energy level. There is a hint of an unwarranted link with geometry using the word level and higher or lower, which can lead to misunderstandings. Don't mix up levels, energy, probability and waves. Again it's the route to confused .com Treat them separately. (My advice)
  21. studiot

    What are your favorite popular science books?

    Well I'm sorry to learn of your difficulties. Is there any way we can help? Also perhaps we should continue this in another thread or PM since it is a bit off topic.
  22. studiot

    Einstein in pre-Nazi Germany

    I think that is a very difficult, if not impossible position to defend. In particular it would imply the 'mathematician' accepted 'instantaneous action at a distance', which Einstein certainly did not.
  23. studiot

    What are your favorite popular science books?

    Not even talking books? Now would be the time to tell us what your favourites are.
  24. There are at leat a couple of current threads where a muddle in the question of equivalence is causing difficulty. I have posted this example for discussion to show that purely mathematical equivalence can be too restrictive.
  25. Not quite the same thing, but I wondered if there was any connection? http://www.techno-preneur.net/technology/new-technologies/chemicals-tec/sodium.html