2d Definition and 1000 Threads

Hello. I was asked to import a number of data to mathematica from an output file for wien2k (based in fortran). The thing is, I have to draw a graph that considers a matrix full of data in three dimensions, but the graph itself should only have two parameters. To sum up: how to represent 3D data...

The result is well known, but i need more details about the integral below \int \mathrm{d}^2x \frac{1}{|\mathbf{x}|} e^{- \mathrm{i} \mathbf{q} \cdot \mathbf{x}} = \frac{2 \pi}{q} I've done the Fourier transform of the Coulomb potential in 3D. But failed to get the right answer in 2D...

Please help As a science fair project, you want to launch an 700 g model rocket straight up and hit a horizontally moving target as it passes 29 m above the launch point. The rocket engine provides a constant thrust of 15.0 N. The target is approaching at a speed of 15 m/s. At what...

Homework Statement Two objects are involved in an elastic collision object 1 has a mass of 20Kg while object 2 has mass of 25Kg the initial velocities of the objects are unknown but neither of the objects are stationary Object 1 is moving 35m/sN30E after collision and object 2 is moving 15...

http://upload.wikimedia.org/math/1/9/8/1983171154842b0b061fc42aa5eb7642.png" How to rewrite this 2D Gaussian eqn in terms of x? i need to calculate the x and y values. let x0=0 and y0=0. is it complex?

I'm trying to plot out the trajectory of an object in a program that is looping through the function and spitting out the x and y coordinates, but I'm having trouble. I want to see a parabola starting at 0,0 going up and ending again at x,0. Basic question: (units aren't critical here f/s m/s...

Please Help, I am not an mechanical engineer but am trying to learn Finite Element Methods to solve a 2D Steady State Heat Conductivity problem. Can anyone point me to an exact solution to the 2D Heat conductivity problem? Please be gentle, I have not had a physics class since 8th grade...

Homework Statement The problem is to obtain the inverse Fourier transform of the following 2D functions F(\mathbf{k})=\frac{k_{x}k_{y}}{k^{2}} Homework Equations The relevant equations are the 2d Fourier transform formulas described...

What I need is a 2d mesh,user specified.I have find some solutions on net but still have problems compiling.Anyone knows wheret o find more?

I need a formula that yields the speed and angle after a 2D collision that uses the coefficient of restitution (e). Preferably this would also be relativistic. I have searched EVERYWHERE for this and could not find it. To "prove" that I have indeed tried I have read the collision sections of...

Homework Statement The steady state temperature distribution, T(x,y), in a flat metal sheet obeys the partial differential equation: \frac{\partial^2{T}}{\partial{x}^2}+{\frac{\partial^2{T}}{\partial{y}^2}}=0 Separate the variables and find T everywhere on a square flat plate of sides S with...

Hi to all! I need to solve following equation: \frac{\partial^2 u}{\partial t^2} + 2 \beta \frac{\partial u}{\partial t} -c^2\nabla^2u=0 It describes a damped wave on a x-y plane. 2\beta is damping factor and c is wave speed. I haven't had any luck finding a PDE class that looks...

I want to make a matrix of values as so: F(0,0) . . . F(1,n) . . . F(n,1) . . . F(n,n) I could of course do it like this list=[] for i in range(0,n): for j in range(0,n): list.append(F(i,j)) a=array(list) a.reshape(n,n) But I am curious if there is a more...

Dear all, Anyone can tell me about the algorithm to write a simple CFD code to solve a flow problem.starting from grid gen, solver,post results. pls refer some site providing sample codes.

Hi, I like to start writing 2d CFD code for laminar flow using SIMPLER algorithm using c. help me from where i get information abt grid generation methods and GUI. If anyone had written such codes can guide me.

Hi, I stumbled upon this dilemma in a homework problem which involved 2D photon gas (unphysical, I know). How many polarization states are there for EM-radiation confined to 2D? In 3D it's 2, but how does it work in 2D? An EM-wave propagating in the z-direction can have its E-component...

Homework Statement Object A has a mass of 2.0 kg and an initial velocity of 2.5 m/s. It strikes Object B, which is at rest and has a mass of 2.0 kg as well. After the collision, the objects travel in different directions, with Object B traveling at an angle of 44 degrees from its...

Homework Statement Two radio frequency sources broadcast waves of the same frequency. They are placed 1.0 m apart. Let the x-axis be the line from one source to the other, and let x = 0 be at one of the sources. Nodes are observed at x = 0.24 m, x = 0.49 m, x = 0.74 m. 1) What is the...

Homework Statement This is for my mechanics class. It seems like it should be easier than I'm making it. A single object of mass m is attached to the ends of two identical, very long springs of spring constant k. One spring is lined up on the x-axis; the other on the y-axis. Chpose your...

Hi everyone, As part of a project, I am required to numerically compute the expression b_{i}^{e} &=& \frac{E_{0}^{i}k_0^2(\epsilon_r-1/\mu_r)}{2\Delta^e}\left[\iint\limits_{\Omega^e}(a_i^e + b_i^e x + c_i^e y)e^{-jk_0 x} dx dy\right] \nonumber\\&&- \frac{jk_0 E_0^i r'}{2\Delta^e...

Hello--- I am reading a paper which presents a method to determine attenuation (and Q factors) from reflection seismic data (Y. Wang, "Q analysis on reflection seismic data," Geophysical Research Letters, Vol. 31, 2004). To perform signal processing on a seismic trace, the paper describes...

Solving 2D Poisson problem with a single series! Conventional solution of \nambla^2u(x,y)=f(x,y) involve solution u(x,y)= \sum_{n=1}^{\infty} \sum_{m=1}^{\infty}E_{mn} sin(\frac{m\pi}{a}x) sin(\frac{n\pi}{a}y) This is a two series solution which is tedious to solve. The book PDE by Asmar...

I've been trying to evaluate an integral for the last few days now and it really has me stumped. I was hoping that maybe someone here would be able to help me out. So the function, cov(x,x'), is fairly basic. It's called a squared exponential covariance function and it evaluates the covariance...

Dear users, I wonder if there is anybody who can give me a hint on how to handle the following situation: In the 2+1 dimensional Klein-Gordon equation with coordinates (t,x,y), I use as initial condition for \Psi(x,0) a spherically symmetric Gaussian. The relativistic dispersion relation...

Homework Statement In a local bar, a customer slides an empty beer mug down the counter for a refill. The bartender is momentarily distracted and does not see the mug, which slides off the counter and strikes the floor 0.40 m from the base of the counter. The height of the counter is 0.730 m...

Homework Statement A rocket is launched at an angle of 53 above the horizontal with an initial speed of 75 m/s. It moves for 25s along it's initial line of motion with an overall acceleration of 25 m/22. At this time its engines fail and the rocket proceeds to move as a freebody. a) What...

hi. i have a quick question regarding fortran 90. i often need to add a vector to a 2d dimensional array, and i find it a bit to 'bulky' to always use do loops. let's say i have this: do i=1, 20 a(:, i)=a(:, i)+b(:) end do is there a simple(r) way to tell fortran that i want to...

I'm trying to do FFT convolution via the FFTW3 library for image processing purposes. Basically I have a kernel and I am convolving it with an image. A problem I encountered has to do with the dimensions of the image. When the width is not equal to the height, the pixel values I get, seem to...

I need a fem code either in MATLAB or fortran to refer to as I am stuck at some places. Please help.

Homework Statement I need to be able to get a equation to figure out the initial speed as an object leaves the origin, and I don't understand what exactly I am suppose to treat these as? Basically they are showing us vectors, Vo being velocity vector, and Vox and Voy being x and y components...

Homework Statement I have a 2D isotropic mass-spring system. The mass is pulled a distance A=1m, and then given an upwards kick with a velocity v_0. The k=1, m=1kg. I need to find the furthest distance from the origin the mass will travel in its orbit. Homework Equations x(t)=A_x\cos(\omega...

the question and solution after i they find the total interval of the total function i can't understand what they do with the graph and how they derive the integrals from it ?

Homework Statement I apologize in advance for my inability to present formal equations here. I'll do my best to be clear with the representation using simple text. "Use the Jacobian Matrix to Prove Laplace's 2D Eq.: (partial^2 u)/(partial x^2) + (partial^2 u)/(partial y^2) = 0"...

Homework Statement A baseball player friend of yours wants to determine his pitching speed. You have him stand on a ledge and throw the ball horizontally from an elevation 3.00 m above the ground. The ball lands 30.0 m away. A) What is his pitching speed? B) As you think about it, you’re...

in a jar we have 3 balls one red one white one black 3 people choose a ball and return it back. x represents the number of different colors which the 3 people chose y represents the number of white balls chosen. p(x,y) find p(2,0) we have in total 27 possibilities 3 people chose...

Homework Statement A small sphere is dropped from rest at a height 'h' above a plane inclined at an angle θ to the horizontal ( < 90degrees ). Given that the sphere loses no energy on impact, show that the distance down the plane between this impact and the next is 8hSinθ. Homework...

we throw 3 coins y represents the throw of three coins x represents the throw of the first two we count the number of hetz gotten from the thrown coins. the solution says for the slot that: P(x=1,y=2)=0.25 but i can't understand how ? the logical solution says: for x to be 1 we have 01 10 so...

Homework Statement A dolphins leaps out of the water at an angle of 35 degrees above the horizontal. The horizontal component of the dolphin's vleocity is 7.7 m/s. Find the magnitude of the veritcle component. Homework Equations I'm not sure what equations to use. The Attempt at a...

Homework Statement A football player throws a football at 40 degrees. A stationary player 31.5m downfield is ready to catch the ball. At what velocity does the player have to throw the ball in order to reach the downfield player? We were told the correct answer is 17.7m/s Homework...

Good day to all, 1) I find difficulty on putting two 2D graphs into one figure. If same command it is easy to do but i have different commands, the commands are listlineplot and plot...

Delete.. Delete..

Homework Statement Plate in the shape of the circular halo (inner radius a, outer radius b>a), the inner edge is being kept at a constant temperature T_0, and the outer at the temperature given by the function f(\phi)=T_0\cos(2\phi). Find the equilibrium distribution of the heat everywhere...

i am now reading the book by landau 'the classical theory of fields' it seems that to develop the relativity theory of einstein, only two postulates are needed the first one is relativity the second is no instantaneous interaction therefore, einstein's theory can be developed in...

Homework Statement Evaluate the following definite two-dimensional integrals over the specified domains of integration. f(x,y)=min(x,y), over the region {(x,y) : 0 \leq x \leq 2, 0 \leq y \leq 1} Homework Equations The Attempt at a Solution I'm not even sure where to start...

As a computer scientist and applied math guy, I've recently taken interest in learning to simulate fluids. I've done simple wave equation and KDV simulations before, but after reading the paper "Rapid, Stable Fluid Dynamics for Computer Graphics" by Kass and Miller 1990. I thought I'd like...

Homework Statement 3. A cannon ball is launched from a cliff with an initial velocity of 50 m/s 300 above the horizontal. If it’s range is 300 m. a)What is the height of the cliff? b) What is the impact velocity of the ball right before it strikes the ground? Homework Equations...

I have two balls with d1 and d2 as their direction, and I have the speed s1 and s2, d1 and d2 are in radians showing the angle made with positive direction of x-axis and in anticlockwise direction i.e 0<=d1 and d2<2*pi their positions are (x1,y1) and (x2,y2) when they collided after...

Homework Statement Consider the 2-dim metric {{\it ds}}^{2}=-{\frac {{a}^{2}{{\it dr}}^{2}}{ \left( {r}^{2}-{a}^{2}\right) ^{2}}}+{\frac {{r}^{2}{d\theta }^{2}}{{r}^{2}-{a}^{2}}}, where r > a. What is its signature? Show that its geodesics satisfy {\frac {{a}^{2}{{\it dr}}^{2}}{{d\theta...

Homework Statement In a Fourth of July celebration, a firecracker is launched from ground level with an initial velocity of 25.0 m/s at 30' from the vertical. At its maximum height it explodes in a starburst into many fragments, two of which travel forward initially at 20.0 m/s at \pm53.0'...

An object is projected horizontally with an initial velocity of 3.0m/s A) When will the vertical displacement be 5.0m B) What will the horizontal displacement be at this time Have difficulty's with A