3d Definition and 1000 Threads

Homework Statement Explain why, as the atomic number increases, the 4s electronic states fill before the 3d states. The fact that they fill first means they are lower energy. You must explain why they are lower energy. Homework Equations The Attempt at a Solution First, I'm aware...

Hi again. Can somebody guide me in find the direction angles of the vector force given below?

Homework Statement Show that x=sin(t),y=cos⁡(t),z=sin^2 (t) is the curve of intersection of the surfaces z=x^2 and x^2+y^2=1. Homework Equations I don't think there aren't really any equations relevant for this maybe except the unit circle..? The Attempt at a Solution...

This is just a coursework question ( I didn't know where to post this). When I find the traces of an equation ( let's say x^2+y^2-z^2=1 for the sake of argument). How does it affect my graph if one part of the equation is an ellipse and the other is an hyperbola? I mean in this case I would...

My book gives a treatment of this problem for crystal vibrations, but I don't really understand it. It says: There is one allowed value of K per volume (2\pi/L)3. But at the same time it has just shown that Kx,Ky,Kz can take values ±2\pi/L which would certainly lead to more combinations of...

Hello! I'm working in a programm which has a 3D array with a DIMENSION(16,221,900). When I use the debugger option and I print out the value of the matrix I don't know how to read the info. I already know Fortran uses column-major order, storing the columns in sequence. My doubt is...

I would like to design a 3D printer. I know that sounds very ambitious (and probably stupidly unrealistic), but I'm not talking about the fanciest things on the market (like glass/metal printers). I just want to design a printer that can print to a great resolution and in mixtures of 3 primary...

Homework Statement knowing the tension in cable AB is 570 N, determine the moment about each of the coordinate axes of the force exerted on the plate at B . This link has a picture...

Hey there, I have a question regarding quaternions and rotations. It's related to 3D graphics programming, but nevertheless I'm sure the physics forum is the right place for my question. As far as I've understood there are 3 primary ways we can store rotation: euler angles, quaternions and...

Homework Statement I'd like to figure out the moment at pt A using the scalar approach, not vector Homework Equations Vector M = r x f Scalar M = fd The Attempt at a Solution I think I might be missing some concept that would make my life easier... I figured out how to...

Why Fe, Co and Ni are ferromagnetic? what aspects of their electronic structure favors ferromagnetism? How 3d or 4f metals can be ferromagnetic and what is their origin of ferromagnetism?

Finite Fourier Transform on a 2d wave How does the finite Fourier transform work exactly? The transform of f(x) is \widetilde{f}(\lambda_{n}) =\int^{L}_{0} f(x) X_{n} dx If I had a 3d wave equation pde and I applied Finite Fourier transform on the pde for z(x,y,t)=X(x)Y(y)T(t)...

hi. I am new at maxwell. i have work on some examples but i want to learn how can i do a linear motor project. i didnt find any examples ( pdfs ). where can i find some pdfs?

OK so I am a bit confused. I am doing multiplication of vectors. I am a bit confused about the angles between two vectors. Let's say a(vect)=(3.0)i-(4.0)j; b(vect)=(2.0)j+(3.0)k in unit vector notation. Or generally how are angles between two vectors in 3d defined. Not just in terms of the dot...

Homework Statement Uploaded Problem 2.1 Homework Equations Etotal=Eq1+eq2 The Attempt at a Solution On problem 2.1 I need quite a bit of help here. I am not really sure how to approach this I have done some work but it is highly incorrect. I hand wrote my solution, so I will upload...

Hi! I am trying to compute the natural frequency of a system and I also need to add the added mass term to my equation. The object I have is a torus and is basically in heaving motion. I found a good paper, which gives a formula for 3d added mass and 2d added mass. I would figure that I...

hi. I am new at maxwell 2D and 3D. i found some pdfs and examples. I am working on the rotational actuator example which in that pdf 1. and i got an error: Fatal internal error (2:14:49 Eyl 09, 2013) Simulation completed with execution error on server: Local Machine. (2:14:49 Eyl 09, 2013)...

Homework Statement I know pictures aren't the best, but here it is. Homework Equations The Attempt at a Solution This is my work for this problem. Disregard the drawing as it isn't right. I'm not sure if I'm misinterpreting the horizontal range part or what. I feel pretty...

Homework Statement Uploaded Homework Equations Uploaded The Attempt at a Solution I actually need someone to check my work for 1.1 and 1.2. Is what I have done in 1.3 correct I mean it does not seem right?

Many of the numbers that define us and our world are beyond the scope of linear counting. If you count a billion seconds, it is more than 32 years, but if you can visualize them as a cube, it has sides of 16 minutes and 40 seconds. A billion millimetre cubes in a line span 1000km, but if you put...

Considering d=2 or d=3, the Ising model exhibits a second order phase transition at the critical temperature T_c, where the system goes from an ordered phase (spins preferably aligned in a certain direction) to a disordered one. This is reflected by the behaviour of the susceptibility, similar...

I have a complicated 3d nonlinear differential system which I solve algebraically using maple's solve command. I aim to find the equilibrium points of the system using MAPLE and then plot these equilibrium points as a function of the 3 parameters alpha,beta,gamma(a.k.a.bifurcation diagram). The...

Homework Statement Find the correct image produced by the concave lens. F is focal length. Homework Equations If an object is placed between F and 2F, the image will be inverted, real, larger and beyond 2F. The Attempt at a Solution I choose the answer A. Is it correct? *Please...

This is my summer homework and my teacher gave us some new stuff to learn. Homework Statement 1. A room has dimensions 3.00 m x 3.70 m x 4.30 m. A fly starting at one corner flies around, ending up at the diagonally opposite corner. a) What is the magnitude of its displacement? b) Could...

Hi all, I'd like to solve the following problem in 3 dimensions: \partial_t u(r,t) = D\Delta u(r,t) u(r,0) = 0 u(0,t) = C_o In words, I am looking at a point 'source' that is turned on at t=0 and held at constant temperature. The ultimate goal is to then convolve this solution with...

Hi, I am using a Human body model which I built for some simulation studies. I was trying to pass DC current through the Human body and though my Project completed the simulation successfully I got the below warning message. Can anyone please help me interpret it? The error log is as...

Hey! I have been trying to solve this problem without success. Any help will be appreciated Homework Statement Resolve the 170 N force into three parts: one of which is parallel to OQ, another parallel to OP, and the third parallel to the y axis. (See the graph) Are these the components of F...

Greetings PFers, I was thinking about methods of delivering mediums used in 3D printing process, specifically 'selective laser sintering'. Currently SLS uses layers of fine metal powder which are fused together, layer by layer. A new coating of powder is applied every layer. Afterwards, the...

Hey guys, I have been reading some articles recently and I have came acrossed an article that the SMRC (Systems and Materials Research Corporation)(with its support from NASA) has a grant that supports its project in creating 3D editable food (pizza) using 3D printing (apprently one of the...

Testing for chaos in data I have data for 3 variables ,each with respect to the discrete time values. How do I check for the existence of chaos for this discrete 3D system?(I don't have the analytic eqs.,just the data.) MY IDEAS ON CHECKING FOR CHAOS FROM DATA:(which of these are feasible...

1. Calculate the internal energy of a system of N classical anharmonic tridimensional oscillators of potential energy V(r) = k*(r^a) with k>0 a>0 and r = abs(r). Verify the result with a = 2 .

I was looking at this demonstration of a new kind of 3D printer: and I was wondering if this approach to 3D printing could be useful for creating structures in space, perhaps in Low Earth Orbit. I was wondering how these tensile types of structures could be put to practical use in space...

Homework Statement I'm trying to prove that the Harmonic oscillator wave function doesn't change (except a phase factor) when I convert from position to momentum space. \Phi_{nlm}(\vec p)=(-i)^{2n+l}\Psi_{nlm}(\vec p) Homework Equations \Phi_{nlm}(\vec p)=\frac{1}{(2\pi)^{3/2}}\int d^3r...

Hello people, I am interested in tutorials about coil design for Maxwell 3D. If anyone have good material or knows where to find it, let me know. Regards,

Homework Statement Hey! I got this problem about 3D harmonic oscillator, here it goes: A particle can move in three dimensions in a harmonic oscillator potential ##V(x,y,z)=\frac{1}{2}m\omega^2(x^2+y^2+z^2)##. Determine the ground state wave function. Check by explicitly counting that it is...

Homework Statement Find the 3D representation of what I think are the commutators [T_a,T_b] for the SU(2) groupHomework Equations I think the generators(X_i) in SU(2) group are the 3 Pauli matrices, which are 2X2 matrices... I assume I need to find the matrices for these generators as 3x3...

Hello All, Is is possible to the derive pitch, roll and translational acceleration, and the location of pitch and roll axes from a set of tri-axial accelerometers mounted on a rigid body? My initial though is that 3 accelerometers might be sufficient, but not sure. I need to do figure out the...

So to get a better edge on our experiment my professor asked if I could take the pictures from cameras which are mounted at three different locations and use MATLAB to create a 3d picture. I have made no progress as I don't really even know MATLAB well. Is there any code or advice one can give?

Homework Statement i need to calculate the orbital angular momentum for 3D isotropic harmonic oscillator is the first excited state The Attempt at a Solution for the first excited state...

Hello, Greetings! How do I get the convective surface matrix from ANSYS for 3D thermal problem. Consider a volume, where some of its surfaces are subjected to convective boundary conditions. What is the way to get those (only convective surface) matrices generated by ANSYS. Any help in...

I've been trying to wrap my head around 3D rotations and specifically, Euler angles. I thought I had a good understanding of performing multiple rotations, but after writing a Matlab script that graphically shows my rotations, I am not so sure right now. My biggest hang up is whether or not a...

Homework Statement http://imgur.com/x8D2wqO I need to solve for theta and I keep getting the angle 65, using cosine law and pythagorean theorem but the answer key says that the angle is 93. The diagram is not to scale. Is my answer wrong or is the answer key incorrect?

if i have rod of a certain length. let point (a) on one end of the rod and point (b) on the other end. along the rod axially is the X axis, vertically Y axis and Z is the lateral direction.let force prependicular on x -axis at point (b) and move this force to point (a) which will create a...

I saw Iron Man 3D last night, and I wanted to know from those who have watched it or will watch it, what do you think of it? The plot, characters, and production. In my opinion, it was good, but Avengers had better special effects. Iron man however had a better plot.

I read somewhere that a unique line connecting two points does not exist in higher than 3D, is this correct?

So I've been playing with a little N-body code in 3D for gravitational problems and have made an OpenGL visualization to go along with it. I have been generating initial conditions (positions and velocities) using explicit formulas. I was wondering of anyone knew of any resources for getting...

Hi to all. I want your opinion about which software is the most suitable for rendering 3D graphics in order to include these as figures in manuscripts, papers etc. I have seen many papers such as in Nature Physics, Nature Photonics etc that some 3D figures are really awesome. Especially, i...

Hi, I have a mesh whose surface is made up of tesselating triangles. I would like to perform an integral over this surface of the form \int f(\Omega) R(\Omega) d\Omega Where f is an arbitrary function and R is the radius at that point. I have a method implemented but it is not working...

Hi everyone! I would like to discuss the pros/cons and engineering challenges one would face in order to create a 3D printer capable of printing in metal. I have created an open source initiative (linked to below) that deals with this subject, there is quite a bit of information I have...

Hi all, I have a simple question about 3D plotting. Consider this simple loop, which provides y and O for any x. and I am able to plot y vs O for given x. for Omega=0:.01:5 y(i)=(x*Omega^2); O(i)=Omega; i=i+1; end now consider I want to change the value of x, for x=0:.1:3...