Coordinate Definition and 868 Threads

  1. D

    Coordinate systems in the solar system?

    I have read the wikipedia page regarding Celestial coordinate systems and searched on google, but I cannot find any coordinate systems which describe a planet's position in it's orbit. Does there exist such a system? An example use of this system would be in locating the planets in the sky. I...
  2. L

    Parametrization vs. coordinate system

    I am reading Differential Topology by Guillemin and Pollack. Definition: X in RN is a k-dimensional manifold if it is locally diffeomorphic to Rk. Suppose U is an open subset of Rk and V is a neighborhood of a point x in X. A diffeomorphism f:U->V is called a parametrization of the...
  3. B

    X Coordinate in Electric Field System

    Homework Statement Locate the x coordinate such that E=0? Coulomb constant is 8.98755x10^9 N m^2/C^2. The 1.68x10^-6 charge is at the origin and a -8.54x10^-6 charge is 10 cm to the right, as shown in the figure. http://i325.photobucket.com/albums/k398/bdh1613/018.jpg Locate the x...
  4. J

    Understanding the 3 coordinate systems for a Schwarzschild geometry

    Hello, There are 3 main coordinate systems for a Schwarzschild geometry : Lemaitre-Rylov (LR), Eddington-Finkelstein (EF), Kruskal-Szekeres (KS). Thanks to my readings, I know thaht KS coordinates are better than EF coordinates and that EF coordinates are better than LR coordinates. But, I...
  5. Rasalhague

    Coordinate Transformation & Jacobian Matrix

    Is the following correct, as far as it goes? Suppose I have a vector space V and I'm making a transformation from one coordinate system, "the old system", with coordinates xi, to another, "the new system", with coordinates yi. Where i is an index that runs from 1 to n. Let ei denote the...
  6. P

    Galilean Coordinate Transformation (Classical Relativity)

    Homework Statement An observer in an inertial reference frame S sees two cameras flash simultaneously. The cameras are 800 m apart. He measures that the first flash occurs at four coordinates given by X1=0, Y1=0, Z1=0 and T1=0, and that the second flash occurs at four coordinates given by...
  7. B

    Converting partial derivatives between coordinate frames

    Homework Statement Given Cartesian coordinates x, y, and polar coordinates r, phi, such that r=\sqrt{x^2+y^2}, \phi = atan(x/y) or x=r sin(\phi), y=r cos(\phi) (yes, phi is defined differently then you're used to) I need to find \frac{d\phi}{dr} in terms of \frac{dy}{dx} Homework...
  8. M

    Coordinate Transformations Question

    Hi there. This isn't so much a math question as it is a conceptual question. I can't seem to wrap my head around the need for coordinate transformations. *Why* do they need to be done? I think I really need a picture for this, so this might not be the right place to ask, but if you can...
  9. Q

    Left-Handed Coordinate System: Unit Vectors i,j,k

    A friend asked me this question today. It kinda threw me for a loop. The cartesian coordinates system is a left handed coordinate system right, so therefroe they are defined by a left handed coordinate syste correct?
  10. Rasalhague

    Coordinate Chart on Manifold: What is $\mathbb{R}^{n}$?

    In defining a coordinate chart, \left ( U,\phi \right ), U \in M, \phi : U \to \mathbb{R}^{n}, on a manifold M, what exactly is \mathbb{R}^{n}: the set of all n-tuples, a topological space, a metric space, a vector space, Euclidean space conceived of as an inner product space, Euclidean...
  11. N

    Griffiths E&M 3.33 write e-field of dipole moment in coordinate free form

    Homework Statement Show that the electric field of a "pure" dipole can be written in the coordinate-free form E_{dip}(r)=\frac{1}{4\pi\epsilon_0}\frac{1}{r^3}[3(\vec p\cdot \hat r)\hat r-\vec p]. Homework Equations Starting from E_{dip}(r)=\frac{p}{4\pi\epsilon_0r^3}(2\cos \hat r+\sin\theta...
  12. J

    Volume of tetrahedra formed from coordinate and tangent planes

    I have that P is the tangent plane to the surface xyz=a^{3} at the point (r,s,t). I need to show that the volume of the tetrahedron, T, formed by the coordinate planes and the tangent plane to P is indepedent of the point (r,s,t). I have found that P is; \frac{x}{r} + \frac{y}{s} +...
  13. K

    HELP Setting up triple integral in spherical coordinate

    HELP! Setting up triple integral in spherical coordinate Homework Statement http://img517.imageshack.us/img517/9139/83291277.jpg Homework Equations I set up the bound for this problem as following: r=0..2/cos(phi), phi=pi/2..3pi/4, theta=0..2pi, but maple always return an error in...
  14. S

    Coordinate systems for electric fields.

    Im curious about an electric field (somewhere of radius s) inside a solid sphere (radius a) such that: \int E.da=E4\pi s^{2} and Q = \frac{\rho 4\pi s^{3}}{\epsilon_{o}3} What is the difference between using each coordinate system to solve for E? It's just that I've really had to teach...
  15. T

    Another coordinate conversions.

    Homework Statement The actual question is to evaluate the integral. All I need help on is the setting up part. Instead of making a thread for each, I will post 3 integral question with my attempts. Just tell me if you see something wrong from rectangular to spherical conversion...
  16. T

    Changing from rectangular coordinate to sperical

    Homework Statement change from rectangle to spherical coordinate : z^2 = x^2 + y^2 I know that : z = pcos(phi) x = psin(phi)cos(theta) y = psin(phi)sin(theta) there fore z^2 = x^2 + y^2 in spherical coordinate is p^2cos(phi)^2 = (psin(phi)cos(theta))^2 +...
  17. T

    Help Rectangle to Cylindrical coordinate question

    Homework Statement evaluate : \int\int\int_{E} e^z DV where E is enclosed by the paraboloid z = 1 + x^2 + y^2 , the cylinder x^2 + r^2 = 5 I just need help setting this up. I know that theta is between 0 and 2pi Now is z between 0 and 1 + r ? and r is between 0 and sqrt(5)...
  18. T

    Rectangle to Cylindrical coordinate question

    Homework Statement can you explain this conversion, I am not sure. Rectangle coord : \int^{2}_{-2}\int^{sqrt(4-x^2)}_{-sqrt(4-x^2)}\int^{2}_{sqrt(x^2 + y^2 )} F(x) dzdydx = cylindrical coord : \int^{2\pi}_{0}\int^{2}_{0}\int^{2i}_{r} r*dzdrd\theta I see that x^2 + y^2...
  19. R

    Linear Algebra: Coordinate system corresponding to the basis

    Homework Statement In the xy-plane, sketch the coordinate system [ a; b] corresponding to the basis { (1, 1 ) , (1, -1) } by drawing the lines a = 0, \pm1 and b = 0, \pm1. What point in the xy-plan corresponds to a = 1, b = 2?Homework Equations Not sure of any in this caseThe Attempt at a...
  20. O

    Curved spacetime and imaginary coordinate

    In Misner, Thorne, Wheeler: "Gravitation" it is stated on that "no one has discovered a way to make an imaginary coordinate work in the general curved spacetime manifold" (p.51). Can anyone elaborate on this? Right now, I don't get why it wouldn't work and nothing more is said in the book.
  21. M

    Pendulum in polar coordinate system problem

    Homework Statement A pendulum consists of a particle of the mass m and a thread of the length l (we don't consider the threads mass). The acceleration caused by gravity is g. Solve the particles displacement and the force caused by the tension in the thread T in a polar coordinate system. The...
  22. S

    Understanding Coordinate Transforms: Partial Derivatives

    Hey, I am having trouble understanding how you can transform one set of coordinates into another using partial derivatives i just don't get the whole thought process behind it. I came across this while reading about covariant and contrivariant vectors. If anyone can help clear up how this works...
  23. R

    Calculating Position and Angle of a Particle on a 2D Plane

    "Simple" Coordinate Problem Homework Statement The following happens on a 2D X-Y Plane. A particle accelerates at {3t m/s2}i + 4t m/s2}j where t = seconds At t = 0, the position of the particle is {20.0 m}i + {40.0m}j At t = 0, the velocity of the particle is {5.00 m/s}i + {2.00 m/s}j At...
  24. M

    How Is Collision Speed Calculated in a Supermarket Parking Lot Incident?

    Homework Statement On a supermarket parking lot, a car is pulling out and bumping into an oncoming car. The car pulls out with 0.8 m/s, while the oncoming car has a speed of 1.2 m/s. The angle between the velocities is 24 degrees, as indicated in the figure. What is the collision speed...
  25. S

    Transformations Between Coordinate Systems

    Homework Statement The velocity of a ball in an x-y coordinate system is (10, -5) where distance is measured in metres. A second coordinate system, p-q, uses units of feet (1 ft = 0.3048 m). The p-axis is oriented at alpha = 15 degrees relative to the x-axis. The origin of the p-q system is...
  26. D

    What is galileian system of coordinate?

    What is Galileian system of coordinate? I have read the chapter about it by einstein but still can't understand it. Can anyone kindly explain it to me? thanks
  27. T

    Two in-phase loudspeakers on a coordinate plane

    Homework Statement Two in-phase loudspeakers are located at (x, y) coordinates (-3.0, +2.0) and (-3.0, -2.0) . They emit identical sound waves with a 2.0 m wavelength and amplitude a. Determine the amplitude of the sound at the five positions on the y-axis (x=0): with y=0.0 with y=0.5 with...
  28. M

    Coordinate transformation under rotation

    If a system is rotated around Z axis then the new coordinates are X'= xcos() - Y sin(), Y'= Xsin() + Ycos() Z'= Z How is this obtained ?? () --->theta , angle of rotation around Z axis .
  29. L

    How Do You Convert Between Two Coordinate Systems with Different Basis Vectors?

    Homework Statement 2 coordinate systems are given: 1st: \vec{a}, \vec{b}, \vec{c} 2nd: \vec{m}, \vec{n}, \vec{p} in system \vec{a}, \vec{b}, \vec{c} basis vectors of 2nd system have values: \vec{m}=\{2/3, 1/3, 1/3\}, \vec{n}=\{-1/3, 1/3, 1/3\}, \vec{p}=\{-1/3, -2/3, 1/3\} also known that...
  30. T

    16 different spherical coordinate systems

    I've tabulated 16 possible ways of creating different spherical coord systems, and attached an image below to demonstrate them all. They are all spheres, though the coordinate system is different for each one. Assume an orthographic projection. Some are blanked out, since they are similar to...
  31. L

    Length of curve in Polar coordinate system

    I want to caculate length of curve in Polar coordinate system like this: if r=r(a) then length of the curve is [SIZE="4"]∫r(a)da Is this right? if not ,why ? What's the right one ? I konw the way in rectangular coordinate system,I just want to do it in Polar coordinate system .
  32. R

    Vectors and coordinate transformations

    Can anyone explain why it's important to be able to take vectors in an x,y,z coordinate system and be able to transform them into other coordinate systems. Could not all vector considerations be grappled with in the standard x,y,z coordinate systems? How important is this ability to physicists...
  33. 9

    Need help on this coordinate geomeotry question

    So here's how it goes. Find the coordinates of the centre and the radius of the circle x^2 + y^2 - 4x + 6y -12 =0 a)If the circle cuts the x-axis at the points A and B , find the length of line segment AB. My question is , I have actually found 2 points , they are (-2,0) and (6,0)...
  34. I

    Proving the Change of Coordinate Matrix for Left-Multiplication Transformation

    Homework Statement Prove: Let A \in \mathrm{M}_{n \times n}(\mathbb{F}) and let \gamma be an ordered basis for \mathbb{F}^n . Then [\boldmath{L}_A]_{\gamma} = Q^{-1}AQ , where Q is the nxn matrix whose jth column is the jth vector of \gamma . Homework Equations \boldmath{L}_A...
  35. F

    Looking for a good webpage with different coordinate systesms

    Anyone have a good link to a site explaining the different coordinate systems and the jacobian determinant for each of them. Thanks EDIT: I actually just need a website wiht a list of the different transformations ie. polar: x = u*cos(v) y = u*sin(v) v \in [0,2\pi], u \in [0,radius] J = r
  36. M

    How can I convert coordinates from Spherical to Cartesian?

    I do not understand Spherical coordinate system. I'm asked to compare the differences with Cartesian coordinate but I have no idea how to start. So I would like some help that will at least give me a understanding of the spherical coordinate system, thx
  37. P

    Normal coordinate substitutions with periodic boundary conditions

    Could someone plase hep me with normal coordinate substitutions with periodic boundary conditions, I can't see where the 1/N cancels in the attached file Thanks Doug
  38. J

    Vector Coordinate Conversion & Phasors

    I would attempt to solve these questions with "relevant equations", but my questions simply derive from an attempt of understanding class notes. If someone could attempt to help my understanding, that would be great. I've attached the PDF file that contains my corresponding questions...
  39. M

    Transformation of Coordinate Systems

    Homework Statement Find a one-to-one C1 mapping f from the first quadrant of the xy-plane to the first quadrant of the uv-plane such that the region where x^2 \leq y \leq 2x^2 and 1 \leq xy \leq 3 is mapped to a rectangle. Compute the Jacobian det Df and the inverse mapping f^{-1}. The...
  40. B

    Does coordinate system = gauge ?

    Does "coordinate system" = "gauge"? [SIZE="4"]Are "coordinate system" and "gauge" the same thing? What about "coordinate transformation" and "gauge transformation"?
  41. H

    Del Operator for Cylindrical Coordinate

    http://img208.imageshack.us/img208/5153/12802868.png Why is the del operator for cylindrical coordinate the upper one and not the lower one? How does the 1/r term arises?
  42. A

    Geometry in spherical coordinate

    Hi all: I am wondering if there is any book or course note about the geometry in spherical coordinate. Not just the superficial definition and the convertion with Euclidean coordinate. But something like how a line is defined in spherical coordinate in 3D space, how a plane is defined, how to...
  43. Z

    Evaluate the iterated intergal by converting to polar coordinate?

    Help me Evaluate the iterated intergal by converting to polar coordinate: http://www.ziddu.com/gallery/4894419/Untitled.jpg.html
  44. B

    What are the Limits for Computing the Volume of a Cylinder Inside a Sphere?

    Hi Guys, I have been given the coordinates of a cylinder inside a sphere and want to convert to Cylindrical coordinates to compute the volume of the cylinder. Can you please check the limits and integral I have? The cylinder is x^2+y^2= 4 sphere = x^2+y^2+z^2= 9 As its a cylinder...
  45. D

    What is the significance of covariance in general relativity?

    Any relationship between mass, length and time in general relativity can be considered using tensors of Einstein's Field Equations which are independent of the coordinate system used and of the origin of that coordinate system Is there a formal name for such coordinate independence and origin...
  46. M

    Finding AREA in POLAR COORDINATE

    Homework Statement Find the area inside one leaf of the four-leaved rose r = cos2xHomework Equations A = 1/2 antiderivative abr2 dxThe Attempt at a Solution I just need help in finding the lower and upper limits of integration. But besides that, I know how to do the rest. If my integration is...
  47. M

    Coordinate transformation of nabla operator

    Hi all! I am studying the Galilean group of transformations and I'm not sure how to transform the Nabla operator. Consider the 2 transformations: (x,t)->(x+s,t) (x,t)->(Dx,t) and the expression "nabla (x)" where D is a matrix and x, s are vectors I am pretty sure that I have...
  48. R

    Mathematica - Colour each 2D point by a third coordinate for each point?

    I'm looking, as an observer, at imaging accretion discs and tori around Kerr black holes. The image of the disc/torus is projected onto a 2D grid (a CCD if you like) so all lensing effects etc. are implicit. Basically, I can plot the image after determining the (x,y) coordinates in the 2D grid...
  49. T

    Coordinate transformation of contravariant vectors.

    Note: The derivatives are partial. I've seen the coordinate transformation equation for contravariant vectors given as follows, V'a=(dX'a/dXb)Vb What I don't get is the need for two indices a and b. Wouldn't it be adequate to just write the equation as follows? V'a=(dX'a/dXa)Va...
  50. J

    How Does the Change of Coordinate Matrix Transform an Ellipse Equation?

    In geometry the change of variable, x = (2 / sqrt(5))x' - (1 / sqrt(5))y' (#1) y = (1 / sqrt(5))x' + (2 / sqrt(5))y' (#2) can be used to transform the equation 2x^2 - 4xy + 5y^2 = 1 into the simpler equation (x')^2 + 6(y')^2 = 1, in which form it is easily seen to be the...
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