3d Definition and 1000 Threads

I was working on a problem on this domain: E=[x,y,z)\:s.t. \: \sqrt{x^2+y^2}\leq z\leq \sqrt{3x^2+3y^2},\: x^2+y^2+z^2\leq 2] and at some point I wanted to find the intersection of the internal cone(##\sqrt{3x^2+3y^2}=z##) with the sphere of radius ##\sqrt{2}## to find the height z of the...

So, I'm trying to plot a 3D "dipole" (an arrow with a small torus around it basically) in mathematica, and want to rotate it according to Euler angles... I use this code for the rotation matrix: rot[a, b, g] := RotationMatrix[g, {1, 0, 0}].RotationMatrix[b, {0, 1, 0}].RotationMatrix[a, {0, 0...

I am concerned that this question may instead be a philosophical one although if it it mathematical, any insights would be very appreciated. The question is this; could an object of N dimensions exist entirely in N-1 dimensions? In other words, could an infinitely flat object have 3 degrees of...

Dear members, Some days ago, I received the following exercise but I have never studied thermodynamics before and I don't know very well where to start, the exercise is about Heat Transfer and the Finite Difference Method and I must program the solution using Petsc and C++. About the Finite...

Hi guys, I have functioning MATLAB code for my solution of the 3D Diffusion equation (using a 3D Fourier transform and Crank-Nicolsen) that runs just from the command window and automatically plots the results. However, it seems like my solution just decays to zero regardless of what initial...

Since the center of a black hole is defined as a singularity and space-time collapses at that point (assumption) is it possible to define this point in 3D coordinates? In other words, is it possible that our universe can not be described as a 3D space but rather as a space with 2.99... dimensions?

Is there any real-world material that is both reflective and transparent in 3D? A simple plane of glass is 3D and transparent, but reflective only in two 2D planes. I'm looking for something that is reflective in a large number of parallel 2D planes so that the reflection has depth. How...

Is it possible to 3d print a neuronal structure with a different material than neurons that would work just like a neuron with membrane potential?

I'm trying to understand how the Navier-Stokes equations are derived and having trouble understanding how the strain rates are related to shear stresses in three dimensions, what a lot of texts refer to as the 'Stokes relations'...

Hey everybody, So I just finished the first version of a personal project I've been working on. This is a simple program that enables you to explore a maze that consists of more than 2 dimensions(to a maximum of 8) in 3d space. It's a simple creature that I'm not sure anyone would really be...

I think I've read the the tensor in three dimensions has 10 elements in its matrix(?). Is this related to the 10 dimensions in some forms of string theory?

I have a particle in a spherical well with the conditions that V(r) = 0 is r < a, and V(r) = V0 if r ≥ a. In this problem we are only considering the l=0 in the radial equation. After solving this I found that in the region 0<r<a, u(r)=Bsin(kr) (k=√2mE/hbar), and in the other region...

Hi PF/math ! I've been searching for a program which will draw 3d parametric curves accurately for large variables, eg. f(10^8). Ive tried www.math.uri.edu and Ti-Nspire (the latter may or may not have a setting for the accuracy), but both tend to turn what should've been a smooth curve into an...

Can somebody provide a solution for this question? convert 3 dimensional unsteady compressible NS equations to axisymmetric 2 dimensional incompressible laminar form for a cylindrical pipe, then make a derivation of streamwise velocity profile u(r) using the appropriate boundary conds. thanks

Hi there, I'm doing a bit of amateur scale model making as a hobby, building shapes out of flat-cut pieces. Trigonometry is a huge help with this, but I've hit a snag where I'm trying to calculate the angle of a particular parallelogram so it fits with the rest of the geometry. 1...

Hi! If I have points A and B in a lattice in the plane, and the closest path between them is n + m steps (for example 4 steps upwards and 5 steps to the right), there are C(9,(5-4)) = 9 combinations of paths between them. I have to choose the 4 ways upwards (or the 5 ways to the right) of the 9...

Homework Statement Requirements: http://i.imgur.com/2WKyhto.png Homework Equations 2(L * W + L * H + W * H) SA = (2 * pi * radius * height + 2 * pi * radius^2) height = (volume)/(pi * radius^2) The Attempt at a Solution Code link: http://pastebin.com/sKFEGN0C

Hi folks!First of all, English is not my native language so I hope there is not much misleading spelling mistakes, discrepancies and inaccuracy. I’m currently working with a hobby-project of a flying drone/UAV with two adjustable angled rotors. I’m able to make it fly more or less in a way it...

Mobile, airborne, and terrestrial 3D laser scanning gives an unprecedented amount of data to companies, organizations, and governments. However, I am wondering whether or not 3D laser scanners have ever been used in astronomy, astrophysics, and in astrocartography... If they haven't, I believe...

For a Mechanical Engineering student, which one is the most needed skill? Illustrator (which can create a cutaway illustration of a car such as below image) or a 3D modeler (which can create a 3D surface model of a car)?

Hello all, I am in the process of calculating reaction forces on an object, and need some help. Attached is a free body diagram of an object in two different views- one looking from the sides (z-x plane) and one looking it in birds eye view. (xy plane) 7 variables I am looking to solve are...

Homework Statement The 1.1m bar is supported by a ball and socket support at A and 2 smooth walls. The tension in the vertical cable CD is 1kN. Draw the Free Body Diagram of the Bar. Determine the Reactions at A and B. Homework Equations Equillibrium equations. Perhaps the vector...

1. I ´m trying to do the dimensional analysis of the Delta Dirac in 3 Dimensions. [PLAIN]http://[url=http://postimg.org/image/oif09fcd5/] 3. This is my atempt [PLAIN]http://[url=http://postimg.org/image/4qavbtv4p/]

What I mean by this is what's the 3d equation of the alcubierrie warp effect? You know when space is contracted infront of the ship, and inflated behind it in terms of z like this eqaurion for a rain drop z=(sin(2x+y)+sin(5y+2x))/5? Here's the photo if you don't understand what I'm talking about...

Dear All, i am new to Maxwell 3D software. i want to simulate my Wireless Power transmission Project in Maxwell, for this purpose i took help from different toturials whic abled me to draw the Tx and RX coils...i want to simulate these coils to calculate the values of L, M, K and etc. but i am...

I am working on implementing a PDE model that simulates a certain physical phenomenon on the surface of a 3D mesh. The model involves calculating mixed partial derivatives of a scalar function defined on the vertices of the mesh. What I tried so far (which is not giving good results), is this...

Homework Statement Consider a system of rotors, each of them placed at one node of a 3D cubic lattice. The system is known as a Heisenberg spin model. Each rotor is represented by a vector of unit length ##\mathbf S(\mathbf r)##, where ##\mathbf r## is its position on the lattice. The...

Hello everyone I am sure the answer to this would be on the internet but I can't seem to find much. When we create a complex 3d cad (examples include Aerodynamic Helmet of a cycle biker, computer mouse, exhaust fan blades etc) that includes complex surfacing in cad, how does one communicate...

Homework Statement I'm trying to write a program to solve a system of 3 non-linear equations using the Newton-Raphson method. I'm stuck on trying to figure out what the formula for a system of 3 unknowns is. I can't remember the derivation at all and after endless hours of googling and looking...

Homework Statement The steel beam is supported by cables AB and CD and a ball-and-socket joint at O. The position of the vertical point load, P influences the reaction at O as well as the tension in each cable. First you need to derive the equations for the tension in cable AB, the tension in...

I am searching for a site that enables me to plot a function of multiple variables in 3D form. Say f(x1,x2,x3,x4) and I wish to plot this function as a 3D graph for x1 and x2 where x3 and x4 are kept constant.

Homework Statement Bead B has negligible weight and slides without friction on rigid fixed bar AC. An elastic cord BD has spring constant k = 3 N∕mm and 20 mm unstretched length, and bead B has a force of magnitude P in direction BC. If bead B is positioned halfway between points A and C...

I've forgotten a lot of field theory so I've been rereading it in a couple of electric field theory textbooks. What seems like a simple problem falls between the cracks. I hope some readers can help - it will be appreciated. My application seems simple (solution will require numerical FEA but...

Homework Statement The problem asked me to derive an expression for the stationary wave function of the 3d harmonic oscillator which I have done. It then tells me a particle is in the stationary state $$\psi_{n_x,n_y,n_z}(x,y,z)=\psi_{100}(x,y,z)$$ and to express this in spherical coordinates...

I'm attempting to create a velocity profile for M31. I have a Sersic profile from a paper by Sofue et al (2009), but I'm unable to project it into 3D space in order to get the actual 3D density that I'd use to calculate the velocity at a given radius. Here's the formula from a 2008 paper by...

Hi! is there anyway to calculate inertia in 3d? for all forms, like we do in 2d, is it the same? https://upload.wikimedia.org/math/d/d/3/dd3b5877d05c86142f03703ac1c6562b.png

Hi, Given a 3D object in R3 space can we represent it using three basic primitive shapes like Sphere, Cone and Cylinder? Would this claim be valid?

Homework Statement A (0,0,0) B(5,6,1) C(3,0,4) |F|= 1919N Homework EquationsThe Attempt at a Solution Cartesian: B= {5i + 6j + 1k} C= {3i + 4k} rCB ={2i + 6j - 3k} |rCB| = sqrt(22 + 62 + 32) = 7 Unit vector = rCB / |rCB| = {2/7i + 6/7j - 3/7k} F = |F| * Unit vector = 1919 {2/7i + 6/7j...

Apologies up front for the long question … I have tried to be brief. I want to define camera angles for Google Earth (GE) when rotated about an aircraft yaw axis. The input is Latitude, Longitude, Altitude plus Heading, Pitch and Bank angles, actually coming from Flight Simulator. These drive...

I know that slope in 2D = $$\frac{\Delta{y}}{\Delta{x}}$$. But what about 3D slope? I mean for every line in 3D there are 3 2D slopes. Those are: $$\frac{\Delta{y}}{\Delta{x}}$$ $$\frac{\Delta{y}}{\Delta {z}}$$ and $$\frac{\Delta{z}}{\Delta{x}}$$ But how do you combine those 3 slopes to form...

I've recently created a 3D motion generator (Anti-Gravity Transportation (AGT)) in 2D/3D design. unfortunately my current physics knowledge is not advanced enough to take this machine to its maxium potential. i can concieve perpultion and sustainable energy coming from this idea. my question...

Good day, I am trying to calculate the stress along the yy-direction for a 3D object compressed in the zz direction (perpendicular to it). The width of the object (in the yy direction) is constant, and the object can only deform along the xx direction. All stresses except for sigma_zz (known)...

The question is as follows: An object of mass m=1 follows the trajectory: r(t) = 4 ln(t) i + 6t1/2 j + 2t k Calculate the force acting on the object and hence find work done between t=1 and t=2. I know that Force = Mass * Acceleration Therefore, F(t) = 1 * a(t) I also know that a(t) =...

Hello, I've just read and I think I have understood the following result : If we were to geodesically transport all points of a small 2D surface, so small that it would be flat for all purposes, in a direction vertically above it, and if this surface belongs in an arbitrary 3D manifold, then in...

Let's say I have point A(2, 6, 0) and B(3, -1, -2) and wanted to find the gradient of the vector joining these two points. I know how to find the vector representing the line joining these points: [FONT=Times New Roman]OA = 2i + 6j , OB = 3i - j - 2k AB = AO + OB [FONT=Times New...

Homework Statement I am using the 3D implementation of Hooke's law as found in wikipedia at: https://en.wikipedia.org/wiki/Hooke%27s_law I need to find the actual source to cite it in a master's project software write up. Many professors do not consider wikipedia to be an acceptable source...

Hello, I have a data file created by an C++ Programm which creates the lines of the data file by an operation inside an loop data3dRnd << gsl_vector_get(x,0) << ' ' << gsl_vector_get(x,1) << ' ' << my_f(x,par) << endl << endl; where the entries of the gsl_vector x are doubles and...

Homework Statement The vertical and horizontal poles at the traffic-light assembly are erected first. Determine the additional force and moment reactions at the base O caused by the addition of the three 100-lb traffic signals B, C, and D. Report your answers as a force magnitude and a moment...

I am very curious about holograms and if there is a possible way to project 3D , mid-air images and videos on air with no holographic screen (The Princess Leia hologram in Star Wars). If it is not possible, how long till they actually start arriving to the world and how will they work/operate?

If we have a cube full of water and glass walls, with an external environmental temperature of 20 degrees celsius, what is the power required to maintain an internal temperature of 25 degrees celsius? Assume sides are 50cm. I don't know what to do, I was trying out the P = (kA/L)(Tf-Ti)...