1. G

    DEbye model

  2. neila9876

    Greenhouse model

    Now is October already. The temperature still can reach 33~34 degree Celsius at noon. About 3 degrees higher than the same period a few years ago. The term "greenhouse effect" is well-known to guys no matter what discipline he majors in. How to cool down the Earth for the survival of human is...
  3. E

    A mathematical model for natural cooling of a cup of tea/coffee/ etc.

    hello I have some problem modeling an approximate model of natural cooling of a cup of tea/coffee left in a closed and controlled room. I attached a detailed PDF document (called 01.10.19) that describes all the details regarding the questions I am going to ask below. 1st questions...
  4. J

    Simulations of Kuramoto Model

    I'm trying to understand and computationally model the Kuramoto Model. This is a mathematical model used to describe synchronization (phase locking of a set of $N$ oscillators). The governing equations: $$\frac{d \theta_i}{dt} = \omega_i + \frac{K}{N}\sum_{j=1}^{N}\sin(\theta_j -...
  5. H

    X4 Model of Unit Electrical Charge

    Declarations: This X4 model of unit electrical charge is established in X4 theory and contains some guess of its own. Anybody shall not try to relate other similar theory to it. The major purpose of this model is to explore the logical relationship between chirality, space and charge, anybody...
  6. Z

    Lenz's law - mathematical model of experiment

    Hi, I need help with writing mathematical model of experiment that demonstarate Lenz-s law (the magnet trough copper tube). N7tIi71-AjA I want to write the model and simulate it in matlab/simulink. On the following link there are a mathematical...
  7. avito009

    Proof that newtonian model works in a black hole.

    Lets keep it simple friendly for layman. Proof that newtonian model works in a black hole. Task is to prove gravity is not a fictitious force which makes it clear that it is a real force obeying newtons first law. Observe light when light gets pulled in a black hole the formula for...
  8. NonGrataEngineering

    Sophism-free Atomic Model

    Looking at the currently accepted atomic model I was surprised that one important element is missing: electron is in constant movement thus as a charged particle is must produce some magnetic field. Let’s take a look how it will affect our understanding of the atom. Read the full article …
  9. E

    Mechanical model of pole-vaulter

    Hello there! I have a small problem with understanding equations from the article that I am making presentation of. If there was a person, who would like to explain me them, I would be grateful. Link for the article (from Journal of Biomechanics): I understand that...
  10. E

    Kronig-Penney model (attractive potential)

    Hi all! Can anyone confirm (or point me to literature) that the dispersion relation for the attractive Kronig-Penney potential is correctly given on Wikipedia (
  11. S

    Mathematical model of fabric drying Problem: Fabric is moving with given velocity on a surface heated by condensing vapor and air flows across fabric with given velocity. Air state, velocities, dimensions of fabric, temperatures of surface and air are given, also initial mass of fabric per m2...
  12. T

    How to make my model running permanently

    Dears, I have interesting model here I need your opinions to improve it so that it will never stop, and run permanently Thanks
  13. L

    moment for 3D model

    in this case( involve 3D model) , it give the moment about the x , y , x' and y' axis .... can we find the moment about a specific point? (i.e. can we find the moment about the O ( centroid) ) ?
  14. I

    The Electrostatic Model of Gravity

    This paper is published at: I invite you to become member of my group "ELECTROSTATIC MODEL OF GRAVITY" at linkedin:
  15. B

    Rutherford model and the planetary sistem

    I cant understand how the Rutherford model would explain changes in the radium of electron orbits. Here is what I think: Moment 1 - An electron suffers an atraction force that is balanced with his kinectic energy, so he stays in orbit. Moment 2 - The electron looses energy and the orbit radium...
  16. G

    Stoichiometry Ratio and Tight-binding Model

    Is Stoichiometry ratio important in tight-binding approximation ? i am going to calculate energy band structure of Vanadium dioxide using this approximation, so i have to determine its unit cell first (the unit cell of VO2 is shown at Fig 1). (Figure 1. tetragonal unit cell of the high...
  17. J

    Spin Foam Model

    I find it "spooky" that speed relativity and gravity relativity works for SR and GR. QFT is awesome in its own right but completely incapable of defining gravity even with the Higgs as it was initially described as the particle responsible for particles having mass, not as a "carrier" of the...
  18. M

    Bohr model and energy

    Hi guys, my first post on this forum. I was wondering if anyone could help me crack this nut: Using the Bohr model of the atom: (i) What would you expect the lowest energy transition from the n=2 to n=1 state to be for single electron ions of the following elements. (ii) What would be...
  19. S

    model with mirror

    A book is on a horizontal table. Is it possible to read the book easily in a mirror which is placed exactly perpendicular to the table. What is the required minimum number of mirror to make the model and how to make it? Schematic diagram of the problem is attached. The problem can be thought...
  20. C

    Finding graphs from motion model

    Hello there! I am actually not new to this forum, but I hadn't logged in for so long I guess my account got deleted. So, hi again! :) I have a question. I have a problem where I am given the model: x(t) = 2.5 - 2t + 0.8^2 From this i have to determine the x vs t, v vs t, and a vs t...