Model Definition and 1000 Threads

Hello Everyone, I am designing Simulink model for HIL testing. Basic concept: Input: Throttle angle ----> Injection timing from that I have calculated requested torque (% of max torque)(chekced and correct) Real torque follows requested torque with delay. (long list of conditions depending on...

Hello! I am predicting the peak altitude of a model rocket based on some ground tests. I know that Total Force on the rocket=Thrust-mg-kv^2 but am stuck as to which value for 'v' to use? Is it the velocity of the rocket with the effects of gravity and air resistance taken into account or the...

Homework Statement a gemoetrical similar open chanel model is constructed with 10: 1 , if the model discharged 7m^3 /s , what is the corresponding discharge in prototype? Homework EquationsThe Attempt at a Solution Q = (L^3) / T , [ (Lp^3)/ (Tp) ] / [ (Lm^3) / Tm ] = (Lr^3) / Tr [/B] but...

I know to describe Quantum Mechanical systems we can use: -Schrodinger equation -Feynman Path Integral method -Heisenberg Matrix formulation Well my question is, if you want to calculate molecular properties, and want to understand biochemistry (protein), you have a system with several...

Hello everyone, I am predicting the altitude of a model rocket based on some testing I did where I found the impulse of a little single stage model rocket motor. I am wondering how to incorporate drag into my calculations to make it more accurate. I know D=Cd*rho*v^2*A and I can definitely find...

The following is from my notes: In 1972, a model was proposed by Georgi and Glashow as a candidate theory describing W bosons and photons with Lagrangian $$\mathcal L = -\frac{1}{2} \text{Tr} F^{\mu \nu}F_{\mu \nu} + (D_{\mu} \phi)^T (D^{\mu} \phi) - \mu^2 \phi^T \phi - \lambda(\phi^T...

Homework Statement Modify the model d = 12 sin (30(t-5)) + 14 to match the new data which is as follows; maximum water depth is 22 m minimum is 6 m, and the first high tide occurs at 5:00am. Homework EquationsThe Attempt at a Solution The answer is y= 8 sin (30(t-2)) + 14 Ik it's 8 b/c...

A recent discussion at the Expanding from and eventually to a singularity thread has been both interesting and informative, and it has shown me very clearly that I would benefit from a few good books, rather than the piecemeal approach I've been taking to understanding singularities and the Big...

Homework Statement Assume that there is a deviation from Coulomb’s law at very small distances, the Coulomb potential energy between an electron and proton is given by V_{mod}(r)=\begin{cases} -\frac{q^{2}}{4\pi\varepsilon_{0}}\frac{b}{r^{2}} & 0<r\leq b\\...

Homework Statement Not exactly a homework problem but I tried to predict the spin and parity of (the ground states of) ##^{89}Sr##,##^{97}Zr## and ##^{137}Ba## using the shell model and my results seem to differ from the tables. Homework Equations Parity ##\pi = (-1)^l## Figure 4 seems to...

Hi people, I'd like to simulate a 2d array of atoms/ions under a magnetic field H via the Ising's model. I've read http://fraden.brandeis.edu/courses/phys39/simulations/AsherIsingModelReport.pdf to get an idea on how to proceed. I'm not sure I got the correct ##\Delta E## values though. I'm...

I'm curious about contact forces, such as the normal reaction force on a book resting on a table. I've read that it's actually the electromagnetic force, but atoms are electrically neutral and there is no ostensible repulsive force between electrons and the nucleus, so I have some doubts. Has...

Homework Statement In the kinetic model of an ideal gas, it is assumed that: A. The forces between the gas and the container are zero B. The intermolecular potential energy of the molecules of the gas is constant. C. The kinetic energy of a given gas molecule is constant D. The momentum of a...

I have been struggling to solve the following problem for days. I was given the state space model of a circuit and asked to determine the system elements. So basically, I think I have to find a suitable circuit which describes the state space equation. I am not really sure how to approach this...

<< Moderator's note: thread spun off from https://www.physicsforums.com/threads/radiation-from-a-square-loop-of-current.868648/ >> But Sir, then why was Rutherford's atomic model rejected by physicists?

The problem is a simple n-body problem: there is n charged particles - electrons, protons, or other particles; we have the initial parameters: a mass, charge, position, velocity, at a time t = 0. In a standard (classical) numerical computation of the n-body problem I can use any numerical...

Can we use the Zig-Zag model of the electron to get an intuitive understanding of the difference between helicity and chirality? Suppose we have a long and narrow cylinder where the spin 1/2 massless zig and zag particles bounce between the top and bottom of the inside of the cylinder at the...

I'm using the general Hubbard model (H = U \sum n_{i,\uparrow} n_{i,\downarrow} - t \sum (c^{\dagger}_{i,\sigma} c_{i+1,\sigma} + c^{\dagger}_{i+1,\sigma} c_{i,\sigma})) to solve for eigenstates of simple quantum dot configurations. For the case of a double dot with two electrons in singlet...

Hey folks. I've done a little bit of research into model rocketry and I'm stuck with the idea of designing and projecting a rocket to put into practice all the engineering I'm learning in college - I'm into MechE. I want to start simple, doing a few tests and learning the basics - types of...

Homework Statement Two objects are connected by a light string passing over a light, frictionless pulley as shown in the figure below. The object of mass m1 = 4.80 kg is released from rest at a height h = 4.40 m above the table. (a) Using the isolated system model, determine the speed of the...

I have to make an oil rig model with the size of 60x50x50cm by using recycled materials and weight will be added from 1 kg to 10 kg depends on its stability. How can I make this model float? thank you

Homework Statement There are several parts to this question, however I could complete these parts. It is just an equation used in the prior part to the question that is need to solve this: If we define \begin{equation} \sigma_{n}^{-}=\sigma_{n}^{x}+i\sigma_{n}^{y} \end{equation} and with the...

Hello everyone i want to model viscoplasticity using Ansys APDL, Perzyna and Peirce or Anand model offer us to do this modeling, and each modèle Contains different parameters. the question is: how to determine the parameters (if we can determine them experimentally, what is the concerned test...

'In the SU(3) quark model there are two singlet vector states $$|\omega_8 \rangle = \frac{1}{\sqrt{6}} \left(|u \bar u \rangle + |d \bar d \rangle - 2 |s \bar s \rangle \right) $$ belonging to the octet and the pure singlet state $$|\omega_1 \rangle = \frac{1}{\sqrt{3}} \left(|u \bar u \rangle +...

Hi guys, I have a question on the fundamental dynamic equation as I am not sure if my equation is correct. I am doing an analysis on a portal crane to find its application factor, somehow I couldn't get the desired value for the velocity of each masses as I couldn't find the tension of the...

I'm practicing for the Physics GRE, and came across a question that has me stumped. "In elementary nuclear physics, we learn about the Fermi gas model of the nucleus. The Fermi energy for normal nuclear density (ρ0) is 38.4 MeV. Suppose that the nucleus is compressed, for example in a heavy ion...

I was looking to find the volume( Rk) and surface area (Qk) parameter for an N-O bond in a pyridine N-oxide molecule?

I am looking for 3D (or 4D, etc.) images of waves (such as light or sound), but seem to be having difficulty locating such models. Can someone please direct me to this kind of display, or is it not something being currently done?

Hi, I have a silly question, Could one, in theory make a accurate model of the life of our universe that one could look at from within. Let's say I put on my VR/AR goggles, 'there' Iam elevated from the earth, then I remain static, and the time begins to rewind. At some point I maybe hear...

I'm a bit confused about how things fill up in the shell model. Here is my understanding: the potential we are working with is the net potential due to the other nucleons that a proton or neutron feels throughout the nucleus; it is a combination of a square and harmonic oscillator potential...

Hello, I am trying to figure out the width of bands in a 1-dimensional lattice. Here is a short derivation from the book I am reading: if we approximate the free electrons as being in a square well then the energy levels are ## \frac{\pi^2 \hbar^2 n^2}{2mL^2}##. If there are ##N## ions...

Greetings, I am slightly curious as to whether the LCDM model may require a slight tweaking. The reason I am curious is because I recall reading a while back that removing the homogeneity assumption from our current models could assist in accounting for some of the large-scale structures, and...

Homework Statement In a double slit experiment, the distance between the slits is 0.2mm and the distance to the screen is 150cm. What is the phase difference in degrees, between the waves from the two slits arriving at point P, when the angular distance of P is 10 degrees relative to the...

Homework Statement Light of a wavelength 548nm illuminates two slits separated by 0.25mm. At what angle would one find the phase difference between the waves from two slits to be 2 rads? Homework Equations σ / λ = ΔΦ / 2π σ: path difference λ: wavelength Δφ: phase difference The Attempt at a...

Dear friends: Put a big disk in the space which can rotate at a speed. for example, if the radius of the disk is 10000km, and it rotates at a speed of 30 rad/s, then the speed at the disk boundary is 30,0000km/s. am i right?

Hi, I'm trying to implement an auto track guidance system for ground vehicles (Eg Tractors), I'm using Matlab and Simulink. I'm at a point where I can calculate heading errors. I'm not too sure how to calculate the lateral errors. Also, I need help in designing the controller. I'm using...

I understand that otical bistability only occurs in a specific parameter regime defined by the bimodial leaf, but I have read that bistability originates from highly non linear dynamics of the system. As we are dealing with a qubit in a cavity that is being driven so things become non-trivial...

From the reading I have done: In the presence of a drive, which is described by an addition term in the Jaynes-Cummings Hamiltonian, the Hamiltonian cannot be solved analytically. The dynamics of the system become non-trivial, with the behaviour depending on the specic parameter regime. So, the...

Homework Statement Program, without any built in functions (like ODE45), a solution to the Blasius Equation in Matlab that outputs boundary layer profiles for given x values, u values, etc. Homework Equations 2f''' + f''f = 0 fj = fj-1 + Δη/2 * (gj + gj-1) gj = [Δη2/4][2gj+1/Δη2 + 2gj-1/Δη2 +...

I've been trying to learn more about the standard model. Leonard Susskind's lectures have been very helpful for SR, GR and QM. His lectures about the standard model are interesting, I learned a lot, no question. But he doesn't really cover in any depth the mathematical side of it. He mentions...

Dear Sir, Assuming that my lottery machine can generate 10 numbers (0..9), in which 0 and 9 are supposed to be starting and ending states of my Markov chain. I apply Markov chain to model each number appearance because I would want to modify the random generation process into, say, my own...

I was trying to determine the bandgap in the nearly free electron model. I'm having trouble to determine the band gap bewteen the second and the third band. Its a one dimensional problem. So, the central equation reads: ##\displaystyle \left [ \frac{\hbar}{2m} (k-G)^2-E \right ]c_{k-G}+...

Hi, Is there a list of basic interactions in the standard model? Does anyone know where I can find this list of basic interactions in the standard model?

Homework Statement I wasn't sure where the most appropriate place to post this question is. But anyway. Which of these, if any, can be used as evidence that the Earth revolves around the sun. 1. The phases of the moon 2. The seasons 3. analemma of the sun 4. solar and lunar eclipses 5. the...

I noticed this in the arxivs, i thought the LCDM model was irifutable but it seems some are trying to better it. arXiv:1602.02103 [pdf, ps, other] First evidence of running cosmic vacuum: challenging the concordance model Joan Sola, Adria Gomez-Valent, Javier de Cruz Perez Comments: LaTeX, 6...

domainwhale submitted a new PF Insights post High Temperature Low Temperature Duality for the Ising Model on an Infinite Regular Tree Continue reading the Original PF Insights Post.

So I'm trying to create a very simple mathematical model for a very idealized theoretical situation of traffic flow. In this situation I'm considering vehicles to be points (no length) each going the same speed with the same distance between them. The vehicle in front (vehicle 1) slows down and...

Homework Statement The state space model of a nonlinear system is x'_1(t) = 2x^2_2(t) - 50 x'_2(t) = -x_1(t) - 3x_2(t) + u(t) Where x_1(t) and x_2(t) are the states, and u(t) is the input. The output of the system is x_2(t). Find the state space model of this system linearized at the...

Help. I'm really struggling with the general idea here. The intricacies of the theory are hopelessly beyond my cognitive reach. I'm just trying to get a general handle on the big picture concept. I read a bit where Lee Smolin referred to this model as a leading theory that characterized space...

This is a kind of cooperative problem solving post. But don't be too terribly 'focused' because likely I have missed important issues. I had not seen a dynamic illustration like this before: maybe I am over impressed, weak-kneed, like seeing Kate Hudson the first time?? In Wikipedia at...