Results 1 to 6 of 6

Math Help - Identify the surface whose equation is given in spherical coordinates

  1. #1
    Newbie
    Joined
    Dec 2008
    Posts
    15

    Identify the surface whose equation is given in spherical coordinates

    Sorry I don't know how to write a nice looking equation on here so, this is the question:

    rho^2 (sin^(2) (phi) * sin^(2) (theta) + cos^(2) (phi)) = 9

    What surface is this?
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Super Member
    Joined
    Dec 2008
    From
    Scotland
    Posts
    901
    Quote Originally Posted by Susaluda View Post
    Sorry I don't know how to write a nice looking equation on here so, this is the question:

    rho^2 (sin^(2) (phi) * sin^(2) (theta) + cos^(2) (phi)) = 9

    What surface is this?
    Just to clarify, this is:

     \rho^2 \big(\sin^2 (\phi) \sin^2(\theta) + \cos^2(\phi)\big) = 9
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Newbie
    Joined
    Dec 2008
    Posts
    15
    Yes, that's right.
    Follow Math Help Forum on Facebook and Google+

  4. #4
    Super Member
    Joined
    Dec 2008
    From
    Scotland
    Posts
    901
    Quote Originally Posted by Susaluda View Post
    Yes, that's right.
    Are you away that, to convert from spherical to cartesian coordinates, you use the following:

     x = \rho \cos(\phi) \sin(\theta)

     y = \rho \sin(\phi) \sin(\theta)

     z = \rho \cos(\theta)

    Some of these bear striking resemblance to your equation, and that might help you to proceed.
    Follow Math Help Forum on Facebook and Google+

  5. #5
    MHF Contributor
    Jester's Avatar
    Joined
    Dec 2008
    From
    Conway AR
    Posts
    2,357
    Thanks
    36
    Quote Originally Posted by Mush View Post
    Just to clarify, this is:

     \rho^2 \big(\sin^2 (\phi) \sin^2(\theta) + \cos^2(\phi)\big) = 9
    Well, if we consider spherical polar coords (US version)

     <br />
x = \rho \cos \theta \sin \phi,\;\;<br />
y = \rho \sin \theta \sin \phi,\;\;<br />
z = \rho \cos \phi<br />

    then I believe it's a cylinder y^2 +z^2 = 9
    Follow Math Help Forum on Facebook and Google+

  6. #6
    Newbie
    Joined
    Dec 2008
    Posts
    15
    Wow, yeah, ok I don't know how I didn't realize that :P Thanks to both of you!
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Wave Equation In Spherical Coordinates
    Posted in the Differential Equations Forum
    Replies: 1
    Last Post: May 4th 2011, 12:37 PM
  2. Replies: 1
    Last Post: March 28th 2011, 10:40 PM
  3. Replies: 1
    Last Post: October 9th 2007, 06:10 PM
  4. Replies: 5
    Last Post: October 7th 2007, 07:10 PM
  5. Identify One More Surface
    Posted in the Pre-Calculus Forum
    Replies: 1
    Last Post: February 22nd 2007, 09:23 PM

Search Tags


/mathhelpforum @mathhelpforum