Questions related to the application of Mathematica to problems in physics.

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2
votes
0answers
93 views

What is a good way to model fluid stream contours around airfoils?

I am an undergraduate student and am doing a project on conformal mapping for my complex analysis class. I have had one heck of a time trying to plot stream function contours to model fluid flow in ...
0
votes
0answers
45 views

Eigenelements of conductivity equation

I am trying to calculate the eigenvalues and eigenfunctions of the conductivity equation in an annulus. In particular I am looking for $(\lambda, u)$ s.t. $$ \begin{cases} \Delta u = \lambda u & ...
0
votes
0answers
29 views

Solving Time-Dependent PDE's Analytically with no non-trivial Boundary Conditions

I'm having some trouble solving a partial differential equation that is supposed to model the propagation of a scalar field in Schwarzschild spacetime using spherical coordinates. I'm using the DSolve ...
0
votes
0answers
33 views

Recycle boundary condition

I'm having the following issue that can not find a solution , by using this boundary condition u[0, t] == 2 u[1, t] that Mathematica does not understand, someone ...
0
votes
2answers
82 views

Jump boundary conditions

I'm having the following issue that can not find a solution , by using this boundary condition ...
0
votes
2answers
78 views

Free-fall air resistance problem

I´m working on a free fall problem and I got an equation with variable $k$ when the situation has air resistance. Then I compared with no air resistance equation ($-4.9$, considering t variable). So, ...
-1
votes
1answer
39 views

Solve returns empty list on system of 62 linear equations with undeclared known variables

Context: I am trying to solve a set of equations generated by hand from a complicated, but not particularly strange system via Newton's Second and Third Laws, and a few constraints. All the resulting ...
0
votes
1answer
58 views

Verify angle pi/4 maximizes launch range [closed]

I'm solving the equation of motion for a projectile in the x, y plane and got this: R = v0^2 sin(2 theta) / g where R is the range of how far the object will ...
5
votes
2answers
249 views

Lagrangian to Hamiltonian

I want to go from Lagrangian description to Hamiltonian one. Using the example given by Mathematica I do something like : ...
2
votes
1answer
122 views

Controlling scaling of multiple vector fields in VectorPlot3D

I'm trying to plot the electric and magnetic fields of a relativistically moving electric charge using VectorPlot3D, and apply "Manipulate" to change the velocity. The code I'm using is as follows: ...
0
votes
1answer
91 views

Plotting graphical analysis of chaotic behavior

I am trying to plot some results of chaotic behavior in a system based on a paper for one of my classes. I am a physics undergrad. I found some sample code online springy.nb which I have been trying ...
0
votes
3answers
168 views

Can I convert a 3-D plot into a 2-D plot?

I am studying the Landau Free Energy Equation. First of all the plot displayed only shown negative range. can i show the positive range too? (y-axes). Then, can I turn this plot into 2-D Plot? ...
-1
votes
1answer
53 views

NDSolve and vectors [closed]

I think I can't find solution of equation below because I need use scalars, not vectors as I have tried. But I don't know how I can do express the problem with scalars. I have read Wolfram Language ...
22
votes
1answer
260 views

How to model wooden joints with mathematica's FEM?

This is a dovetail joint: and I'd like to see the stresses and deformation on the joint.I haven't seen any modeling of disconnected regions with FEM, only connected regions, so I'm curious if you ...
12
votes
2answers
297 views

Sampling a phase space uniformly for a given energy?

The energy for a 1D harmonic oscillator can be written: $$ E = \frac{1}{2 m} p^2 + \frac{m \omega^2}{2} x^2 $$ where x is position and p is the momentum. I would like to sample phase space $(x,p)$ ...
1
vote
0answers
91 views

How to find the eigenvalues of a custom operator using NDEigensystem? [closed]

I would like to solve a Hamiltonian presented by a 2x2 matrix. Hamiltonian is given by: ...
0
votes
1answer
108 views

Animate spherical pendulum

I want to plot the position of Spherical pendulum. First I tried to plot the simple pendulum: ...
0
votes
1answer
115 views

How can I solve a Hamiltonian with numerical methods?

Hamiltonian in terms of two level atom's operator (0 is ground state and 1 is excited state) which are 2*2 matrices and cavity modes are given by $a$ and $a^\dagger$. Rest of the parameters are ...
0
votes
2answers
77 views

Determine the initial speed and launch angle of a projectile from its trajectory

I have the coordinates {x,y} needed to plot the trajectory of a projectile, which are given below: ...
6
votes
0answers
198 views

Problems with NDSolve for solving coupled Schrödinger-like PDEs with perfectly matched layer boundary condition

I'm trying to solve a full-vectorial wave equation for an arbitrarily shaped wave guide, by using NDSolve and perfectly matched layer (PML) conditions. The PML ...
2
votes
1answer
116 views

Improving the speed of evaluating numerical solution to a sytem of PDE

I am running a simulation for a kinetic reaction inside a pellet modeled by a system fo reaction-diffusion equations. ...
8
votes
1answer
121 views

Beam deformation due to localized force distribution

I would like to simulate the deformation of a beam which is fixed on one end and has some localized forces applied along the top. I have been inspired by this Mathematica example: ...
9
votes
3answers
597 views

Calculate inertia tensors

Moments of inertia and inertia tensors are well-known characteristics of rigid bodies in physics and applied mathematics. How to calculate them in Mathematica? Is possible to use regions which was ...
30
votes
2answers
2k views

The Orbit and Perigee of the Flamsteed comet

Historical context This year we have the 330-th anniversary of the Battle of Vienna - one of the great formative events of European history, it took place on September 12, 1683. Kara Mustafa, Grand ...
5
votes
2answers
243 views

How to see phase difference of two pendulum

i want to see the simulation of two uncoupled Simple Harmonic Motion (SHM) pendulum with different Lengths and released at different initial displacement angles. in this case adding one more pendulum ...
2
votes
2answers
86 views

How to make A simulation of 2-Dimensional Projectiles

Lets say two cannon is fired at different initial position, initial angle and initial speed. let say initial speed,angle and position for projectile 1= ...
0
votes
1answer
75 views

Making a Manipulate showing a the motion of a particle [closed]

Solving a differential equation I got to the following result -(((R[n*Pi - t/w] Cos[t/w])/(n*Pi)) Then, using this solution, I create . ...
1
vote
1answer
154 views

Boundary Problems

I am trying to study what happens to a wave as it passes different boundaries. This is the working wave equation defined on a plane ...
1
vote
1answer
167 views

Raman spectra collected at over 200 spatial points and in separate text files, how can I collate and visualize the data?

I need to do density plot and contour plot of Raman spectra with a specific peak, Raman mode, as a way to study the intensity distribution of such peak throughout the sample used. As such ...
9
votes
1answer
1k views

Schrödinger eigenvalue problem in two dimensions (Harmonic Oscillator)

I read here the discussion about how to solve a one-dimensional eigenvalue problem. I am wondering, how can one generalize these methods to two dimensions? For example, how to solve this equation: ...
0
votes
2answers
230 views

A function generating particle-in-a-box eigenfunctions

This function sequence is defined over $\left[-\frac{L}{2},\frac{L}{2}\right]$ (all elements are valued 0 outside this interval): $$\psi_n(x)=\begin{cases}\sqrt{\frac2{L}}\sin{\left(\frac{n\pi ...
3
votes
0answers
168 views

How to solve the Tsunami model and animate the shallow water wave?

Recently when I was learning differential equations, I noticed there is a shallow water wave equation to model the tsunami propagation. How to establish and solve the initial and boundary conditions ...
0
votes
1answer
143 views

Plotting a Double Sum

I am attempting to plot a graph of a function that is the absolute value of the double sum of an exponential function, and I keep getting errors. Here is the code: ...
16
votes
1answer
500 views

How to numerically solve a 1-d time-independent Schrödinger equation?

The point is to solve the eigensystem of the given Hamiltonian. I tried ParametricNDSolve combined with FindRoot to search for ...
1
vote
1answer
199 views

Ball rotating in a Turntable

I made a turntable to make some experiments and make some studies about Coriolis and Euler forces acting in different frames of reference. ...
2
votes
0answers
144 views

Schrödinger equation for Hydrogen atom [closed]

I'm trying to solve Schrödinger 1D equation for hydrogen atom but I found several difficulties. To get in context I want to solve this equation For Z and l real and arbitraries. To start with I ...
11
votes
3answers
507 views

Using NDSolve to find particle trajectory

I'm trying to simulate a particle in an electric and magnetic fields, but numerically instead of analytically. This is basically solving the equation $$q \cdot \left(p'\times B\right) + q\cdot E = m ...
1
vote
1answer
120 views

Phase Portrait to Differential Equation [closed]

I posted this question on Math.SE and have received a satisfactory answer in the context of that website. I am re-posting it here to get input from Mathematica users. Why would I receive a different ...
9
votes
3answers
276 views

Labeling solutions of an Eigenvalue equation involving Bessel functions

I'm solving the Schrödinger equation for a particle in an annular geometry with hard wall boundary conditions and I've reduced it to the following equation: $$J_m(k\,R_1)\,Y_m(k\,R_2) - ...
10
votes
0answers
153 views

How best to simulate n-body systems in a functional way

I want to simulate a N-body system in the most functional way possible. The system I'm modeling are metallic colloidal particles in a solution of peroxide water, as here ...
2
votes
1answer
45 views

Get Isotope Data and Electron Mass in Same Units - kg and Kilograms

I'm trying to find the nuclear mass of $^{238}\text{U}$. To do this, I subtract the electron mass from the atomic mass. I'd like to find the final answer in kilograms. I'd also like to use ...
0
votes
1answer
47 views

Problem in trying to solve a differential equation [closed]

I'm trying to solve a differential equation but not getting a solution. Some references I read gave me hits about using a runge kutta method. I'm new to the software, any hints regarding this error ...
4
votes
1answer
165 views

Recognize physical constants?

Is there some way to ask Mathematica to recognize physical constants, such as 32 or 9.81 (gravitational acceleration, in different units, at Earth's surface)? I have in mind something like the ...
6
votes
0answers
142 views

Heat convection differential equations from 1952 - Mathematica “fails to converge”

I am trying to solve a fundamental problem in analytical convective heat transfer: laminar free convection flow and heat transfer from a flat plate parallel to the direction of the generating body ...
5
votes
2answers
215 views

Solve numerical differential equations at `t->Infinity`

I have a first order non-homogeneous system of differential equation (100+ equations, so no hope to solve them analytically, due to the Abel–Ruffini theorem). If I solve them using ...
7
votes
1answer
265 views

Synchrotron Radiation and ListDensityPlot

I'm trying to reproduce the following plots: As described by this blog entry: Synchrotron radiation As you can see in the linked article, the task is essentially to make a ...
1
vote
1answer
324 views

How can I use Mathematica to solve a Stefan Problem using an explicit scheme?

I would like to plot the temperature distribution for a particular case. the problem is stated in the paper, behind a paywall here, summarized as Consider a one-dimensional container of length l, ...
8
votes
2answers
288 views

Boson commutation relations

I have tried to adapt this answer to my problem of calculating some bosonic commutation relations, but there are still some issues. The way I'm implementing the commutator is straightforward: ...
2
votes
3answers
727 views

draw part of parabola using graphics

today I was doing my physics homework. one of the questions was draw velocity-time and position-time graphs from the acceleration-time graph. So for the first step I draw acceleration-time using ...