Polar Definition and 1000 Threads

  1. I

    MATLAB Matlab polar to rectangular coordinates

    Prepare a function m-file containing a function that converts polar coordinates in two-dimensional space to rectangular (Cartesian) coordinates. Include a suitable H1 line and some additional comment lines. The input will be 2 vectors, and the output will be 2 vectors. The length of each vector...
  2. Dewgale

    Usage of Del in Spherical Polar Coordinates

    Hi all, I'm having some problems in grasping/properly understanding the usage of the del operator ( ##\nabla## ) in spherical co-ordinates, and I was wondering if someone could point me to some good resources on the subject, or take a bit of time to try to explain it to me. It just doesn't seem...
  3. H

    Why HCl is polar covalent compound?

    since HCl dissociates in H+ and Cl- like NaCl then why it is not ionic still?? tell except electronegativity diff?
  4. H

    Online polar coordinate plotter

    Tried to post this in the resources forum but could not start a new thread. I can not find graphing software to plot data in polar coordinates. Anyone got links??
  5. C

    MHB Sketch the curve with the given polar equation. θ = −pi/6?

    Sketch the curve with the given polar equation. θ = −pi/6? I know for certain that its a straight line that passes through the origin but what I'm not sure is if its like this \ or like this /
  6. xpell

    Heliocentric polar orbit crossing the Earth's orbit twice

    Sorry, the title's length didn't allow me to explain this better and I need it for a story that I'm writing, if you're so kind to help me. I've been trying it hard to solve it myself but I've been unable to. The problem looks simple but it isn't (for me): Please assume we have a space probe of...
  7. S

    Understanding the Polar-Cartesian Relationship in Jacobian Calculus

    This is a problem that has been bugging me all day. While working with the well-known dydx = rdrdθ, where r is a function of θ I divided both sides of the equation by dxdθ to get dy/dθ = r(dr/dx) For the left side, I use y = rsinθ and derive with respect to θ to get dy/dθ = sinθdr/dθ + rcosθ...
  8. Elemental

    Spin Operators: Axial for QM, Polar in Clifford Algebra?

    Hello folks! New to this forum, so hoping I'm not retreading old ground. The Pauli matrices are spin angular momentum operators in quantum mechanics and thus are axial vectors. But in Clifford algebra in three dimensions they are odd basis elements and thus polar vectors. Hestenes, Baylis, other...
  9. X

    Polar vector to rectangular equation

    Homework Statement The problem I'm stuck on is to come up with an equation which will model the path of the projectile in an xy-plane. We are given: r(t)={ [(v0cos(θ))t], [h+(v0sin(θ))t-(½)gt2] } v0=100 ft/s θ=60° h=4 ft so basically, r(t)={[100cos(60)t], [4+100sin(60)t-16t2]} Homework...
  10. W

    Finding the Limit of Curvature for a Polar Curve

    Homework Statement Given the polar curve r=e^(a*theta), a>0, find the curvature K and determine the limit of K as (a) theta approaches infinity and (b) as a approaches infinity. Homework Equations x=r*cos(theta) y=r*sin(theta) K=|x'y''-y'x''|/[(x')^2 + (y')^2]^(3/2) The Attempt at a Solution...
  11. icystrike

    Chemistry Understanding Polar Molecules: Exploring the Definition and Characteristics

    Homework Statement Which statement describe a polar molecule? a. The molecule has an uneven distribution of electron density [ans] b. The molecule has a linear polarity without charge c. The molecule has a tetrahedral geometry d. All of the above The Attempt at a Solution I would personally...
  12. Harel

    A problem with polar coordinates and black hole

    Hey, I know that one doesn't work with polar coordinates (t,r,θ,φ) because they don't behave well in the event horizon. But my problem is with raidal null curves, if we take ds2=0 and dφ, dθ = 0 so we have When, if I'm correct, the + sign determine that it's outgoing and the - infalling, so...
  13. S

    Time derivatives of polar motion

    Homework Statement A particle moves with v=constant along the curve $$r = k(1+\cos \theta)$$Find ##\mathbf{a}## Homework Equations $$ \mathbf{r} = r\mathbf{e_r}$$ $$ \mathbf{v} = \frac{\partial}{\partial t}(r\mathbf{e_r}) $$ $$ \mathbf{a} = \frac{\partial \mathbf{v}}{\partial t} $$...
  14. B

    Time derivatives in Spherical Polar Coordinates

    Homework Statement Evaluate r(hat and overdot), θ(hat and overdot), φ(hat and overdot) in terms of (θ , Φ) and the time derivatives of the two remaining spherical polar coordinates. Your results should depend on the spherical polar unit vectors. Homework Equations ∂/∂t= The Attempt at a...
  15. R

    How does a change of variables affect a double integral?

    If we expres cartesian cordinates in polar coordinates we get: x=r*cos(theta) y=r*sin(theta) let's differentiate those 2 eqs: dx= dr cos(theta) -r* d(theta) * sin(theta) dy=dr sin(theta) + r* d(theta) * cos(theta) why isn't dx*dy= r* dr* d(theta) ( like when taking the jacobian , or when...
  16. duran9987

    Motion On An Off Center Circle In Polar Coordinates

    Homework Statement A particle moves with constant speed ν around a circle of radius b, with the circle offset from the origin of coordinates by a distance b so that it is tangential to the y axis. Find the particle's velocity vector in polar coordinates. Homework Equations (dots for time...
  17. A

    Area in polar coordinate using multiple integral

    The question is to find the area of a disk, r ≤ 2a×cos(θ) as in the figure "example-just an illustration" I used two methods, each gave different wrong answers - integrate 2a×cos(θ) dθ dr - from θ=0 to θ=π/2 and from r=2a to r=2a×cos(θ) ; then I simply multiplied the answer by 2. - integrate...
  18. karush

    MHB Find Solution for Polar to Rectangular Equation

    Polar to rectangular $$r=1-2 \sin\left({\theta}\right)$$ $${x}^{2}+{y}^{2}=\sqrt{{x}^{2}+{y}^{2 }}+2y$$ Is this an answer just hard to get $y=$
  19. P

    Changing to polar coordinates in an exponential

    Hello :) I don't get this integral (Peskin & Schroeder P. 27 ) ##\int {{{{d^3}p} \over {{{\left( {2\pi } \right)}^3}}}{1 \over {{E_{\bf{p}}}}}{e^{i{\bf{p}} \cdot {\bf{r}}}}} = {{2\pi } \over {{{\left( {2\pi } \right)}^3}}}\int\limits_0^\infty {dp{{{p^2}} \over {2{E_{\bf{p}}}}}{{{e^{ipr}} -...
  20. M

    Integrating Gaussian in polar coordinates problem

    I have a 2D Gaussian: ## f(x,y) = e^{-[(x-x_o)^2 + (y-y_o)^2]/(2*{sigma}^2)}## which I converted into polar coordinates and got: ## g(r,θ) = e^{-[r^2 + r_o^2 - 2*r*r_o(cos(θ)cos(θ_o) + sin(θ)sin(θ_o))]/({2*{sigma}^2})} ## The proof for how this was done is in the attached file, and it would...
  21. EternusVia

    Why do enantiomers rotate polarized light?

    We are currently learning about enantiomers in organic chemistry class. So far, we've covered what makes an enantiomer, the concept of chirality, optical isomer naming systems, and the physical and chemical properties of enantiomers. One of the physical properties listed is that enantiomers...
  22. flaticus

    What are the non-zero Christoffel symbols for 2D polar coordinates?

    Just started self teaching myself differential geometry and tried to find the christoffel symbols of the second kind for 2d polar coordinates. I am checking to see if I did everything correctly. With a line element of: therefore the metric should be: The christoffel symbols of the second kind...
  23. M

    Polar and Cartesian graphs not matching up

    I have an original function ##z_{xy}## that I converted into cylindrical coordinates, now denoted ##z_{rθ}##. I have shown the steps I took to get here in the image file posted named "Work." Now, I have taken that work and converted it into code to plot in Python. I plotted it in another piece...
  24. S

    Double integral on triangle using polar coordinates

    Homework Statement Let R be the triangle defined by -xtanα≤y≤xtanα and x≤1 where α is an acute angle sketch the triangle and calculate ∫∫R (x2+y2)dA using polar coordinates hint: the substitution u=tanθ may help you evaluate the integral Homework EquationsThe Attempt at a Solution so the...
  25. V

    Converting a unit vector from cartesian to cylindrical

    Hi, I was wondering if anyone could help with a vector question that I have. If I have a unit vector defined in cartesian co-ordinates as p= (0,1,0) how would I go about converting this vector to a cylindrical geometry. I understand that I will probably need to use p_r=sqrt(px^2+py^2) and...
  26. karush

    MHB How to Convert Polar to Rectangular Coordinates in Calculus?

    $r=3-\cos\left({\theta}\right)$ ${r}^{2}=3r-r\cos\left({\theta}\right)$ ${x}^{2}+{y}^{2}=3r+x$ How you deal with 3r ?
  27. YogiBear

    Show that w is solenoidal having spherical polar coordinates

    Homework Statement The gradient, divergence and curl in spherical polar coordinates r, ∅, Ψ are nablaΨ = ∂Φ/∂r * er + ∂Φ/∂∅ * e∅ 1/r + ∂Φ/∂Ψ * eΨ * 1/(r*sin(∅)) nabla * a = 1/r * ∂/∂r(r2*ar) + 1/(r*sin(∅)*∂/∂∅[sin(∅)a∅] + 1/r*sin(∅) * ∂aΨ/∂Ψ nabla x a = |er r*e∅ r*sin(∅)*eΨ | |∂/∂r ∂/∂∅...
  28. K

    Curl of a field in spherical polar coordinates

    Homework Statement I have a field w=wφ(r,θ)eφ^ (e^ is supposed to be 'e hat', a unit vector) Find wφ(r,θ) given the curl is zero and find a potential for w. Homework Equations I can't type the matrix for curl in curvilinear, don't even know where to start! I've been given it in the form...
  29. karush

    MHB How to Convert Polar Coordinates to Rectangular Coordinates?

    $2\sin\left({\theta}\right)-3\cos\left({\theta}\right)$ Convert to rectangular coordinates I'm clueless?
  30. Jimster41

    Are there any "Polar" solar system structures?

    Like asteroid clusters or any kind of what-not thought to be part of our solar system?
  31. I

    Calculating A Double Integral Using Polar Coords

    I'm on a tablet and having trouble with the math symbols so, for clarity, ∫[a,b] xdx is the integral from a to b of x with respect to x, and f(x) |[a,b] is a function of x evaluated from a to b. Problem: ∫[-1,1]∫[-√(1 - y2),√(1 - y2)] ln(x2 + y2 + 1) Relevent Equations: x2 + y2 = r2 ∫udv =...
  32. S

    How to determine rectangular and polar radii of gyration?

    Homework Statement [/B] Determine the rectangular and polar radii of gyration of the shaded area about the axes shown. Homework Equations dIx = y2dA Ix = ∫y2dA dA = ydx A = ∫(dA The Attempt at a Solution dIx = y2dA =(x6/16) *(x3/4) dx =(x9/64)dx Ix =(integrating from 1 to 2) ∫dIx =...
  33. W

    Integrating in Polar Coordinates: Ω Region

    Homework Statement ∫∫dydx Where the region Ω: 1/2≤x≤1 0 ≤ y ≤ sqrt(1-x^2) Homework EquationsThe Attempt at a Solution The question asked to solve the integral using polar coordinates. The problem I have is getting r in terms of θ. I solved the integral in rectangular ordinates using a trig...
  34. S

    Understanding Phasors: How to Sketch a Voltage Phasor in Polar Form

    Hello Excuse me, but how do I sketch the phasor of a voltage that it's V=5cos(10t+30degrees) and how the V=5sin(10t+30degrees) ? I know that these can be converted as the R<angle polar form, with R being the Vmax, ie the 5, and the angle the phase. But what doesn't it matter if I have cos or...
  35. K

    Poisson PDE in polar coordinates with FDM

    I want to solve a Laplace PDE in a polar coordinate system with finite difference method. and the boundary conditions: Here that I found in the internet: and the analytical result is: The question is how its works? Can I give an example or itd?Thanks
  36. M

    Equation (with polar coordinates) of circle on a sphere

    hi, i'm a newbie... i have this problem: i have a sphere with known and constant R (obvious), i have two point with spherical coordinates P1=(R,p_1,t_1) and P0=(R, p_0, t_0) p_x = phi x = latitude x t_x = theta x =longitude x the distance between point is D=...
  37. N

    Path of a Projectile in Polar Coordinates

    Homework Statement A projectile is launched from a mountain at a given angle and velocity (which is large). Using polar coordinates find the position of the particle at time t. I'm ignoring drag (for now). Homework Equations I tried using the polar kinematic equations...
  38. C

    Cartesian to polar unit vectors + Linear Combination

    I've been trying to solve this question all day. If somebody could point me in the right direction I would really appreciate it! (ii) A particle’s motion is described by the following position vector r(t) = 4txˆ + (10t − t)ˆy Determine the polar coordinate unit vectors ˆr and ˆθ for r. [4]...
  39. RJLiberator

    Help me setup and solve double integral in polar coord.

    Homework Statement The region between sphere x^2+y^2+z^2=3 and the upper sheet of the hyperboloid z^2=x^2+y2+1. Homework EquationsThe Attempt at a Solution Curve of intersection: We set the two equations equal to each other and find x^2+y^2=1, a circle of radius 1 is the curve of...
  40. geezer73

    Double Integrals in Polar Coordinates

    I'm in the middle of the Great Courses Multivariable Calculus course. A double integral example involves a quarter circle, in the first quadrant, of radius 2. In Cartesian coordinates, the integrand is y dx dy and the outer integral goes from 0 to 2 and the inner from 0 to sqrt(4-y^2). In...
  41. W

    Force between polar molecule and an ion

    Homework Statement Under certain conditions the interaction between a "polar" molecule such as HCl located at the origin and an ion located along the x-axis can be described by a potential energy U=−bhttps://s3.lite.msu.edu/adm/jsMath/fonts/cmmi10/alpha/144/char3D.pngx^2, where b is a...
  42. P

    Vector components in polar coordinates

    The magnitude of the parallel component of the time derivative of a vector ##\vec{A}## is given by: $$|\frac{d\vec{A}_{\parallel}}{dt}| = |\frac{dA}{dt}|$$ Where ##A## is the magnitude of the vector. Can we write the actual derivative in vector form as ##\frac{dA}{dt} \hat{A}##? Notice how I...
  43. P

    Polar coordinates, sign ambiguity

    The position of a point in cartesian coordinates is given by: $$\vec{r} = x \hat{\imath} + y \hat{\jmath}$$ In polar coordinates, it is given by: $$\vec{r} = r \hat{r}$$ Now, ##x = r \cos{θ}## and ##y = r \sin{θ}## assuming ##θ## is measured counterclockwise from the ##x##-axis. Equating the two...
  44. R

    How Do You Convert Cartesian Vectors to Cylindrical Coordinates?

    Homework Statement I am trying to convert the following vector at (1, 1, 0) to cylindrical polar coordinates, and show that in both forms it has the same direction and magnitude: ##4xy\hat{x}+2x^2\hat{y}+3z^2\hat{z}## Homework Equations ##\rho^2=x^2+y^2## ##tan \phi = \frac{y}{x}## ##z=z##...
  45. RJLiberator

    Partial Derivatives and Polar Coordinates

    Homework Statement Write the chain rule for the following composition using a tree diagram: z =g(x,y) where x=x(r,theta) and y=y(r,theta). Write formulas for the partial derivatives dz/dr and dz/dtheta. Use them to answer: Find first partial derivatives of the function z=e^x+yx^2, in polar...
  46. samjohnny

    Surface integral in Spherical Polar

    Homework Statement Attached. Homework Equations The Attempt at a Solution Hi, Ok, so for the first part of this question it asks to evaluate the integral of the dot product between A and dS. The magnitude of dS is as shown above, and it is in the radial direction in spherical polar...
  47. P

    Kinematics in polar coordinates

    It it bad practice to consider values of ##r## that are greater than or equal to zero, while ignoring negative values? Do I lose any information in my analysis of motion? I understand what values of ##r < 0## represent, and I'm willing to use them in a pure mathematics context. In classical...
  48. AdityaDev

    Electric field due to dipole in polar coordinates

    For a dipole, if there is point subtending an angle ##\theta## at the centre of dipole and at a distance ##r## from centre of dipole, then the electric field at that point can be broken into 2 components. One along the line joining the point and centre of dipole and point given by...
  49. R

    Newton's Second Law - Polar Coordinates

    Homework Statement Given that: theta_dot = 6 rad/sec m_A = 0.8kg u_k = 0.40 The problem also mentions that movement is at a constant angular rate so I think that means: r_doubleDot = 0 theta_doubleDot = 0 Lastly, at an instant: r_dot = 800mm/sec = 0.8m/sec 2. Homework Equations...
  50. B

    Surface Integral, Polar Coordinates

    Homework Statement Express f(x,y) = \frac{1}{\sqrt{x^{2} + y^{2}}}\frac{y}{\sqrt{x^{2} + y^{2}}}e^{-2\sqrt{x^2 + y^2}} in terms of the polar coordinates \rho and \phi and then evaluate the integral of f(x,y) over a circle of radius 1 centered at the origin. Homework Equations y = \rho...
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