Results 1 to 6 of 6
Like Tree4Thanks
  • 2 Post By topsquark
  • 2 Post By SlipEternal

Thread: Help with spherical coordinate question on Phi

  1. #1
    Member
    Joined
    Sep 2017
    From
    nj
    Posts
    196
    Thanks
    1

    Help with spherical coordinate question on Phi

    Help with spherical coordinate question on Phi-capture.png

    not sure about the last question ;/

    How come it isn't 0 to pi?
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Forum Admin topsquark's Avatar
    Joined
    Jan 2006
    From
    Wellsville, NY
    Posts
    11,277
    Thanks
    774
    Awards
    1

    Re: Help with spherical coordinate question on Phi

    Quote Originally Posted by lc99 View Post
    Click image for larger version. 

Name:	Capture.PNG 
Views:	12 
Size:	116.1 KB 
ID:	39081

    not sure about the last question ;/

    How come it isn't 0 to pi?
    In spherical coordinates $\displaystyle \phi$ goes from $\displaystyle 0 \text{ to } 2 \pi$ about the z axis. Since the graph of the cone is around the whole z axis then $\displaystyle \phi$ has the given domain.

    -Dan
    Thanks from SlipEternal and HallsofIvy
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Member
    Joined
    Sep 2017
    From
    nj
    Posts
    196
    Thanks
    1

    Re: Help with spherical coordinate question on Phi

    I've tried [0,2pi] as an answer but it's incorrect.
    Follow Math Help Forum on Facebook and Google+

  4. #4
    MHF Contributor
    Joined
    Nov 2010
    Posts
    3,720
    Thanks
    1515

    Re: Help with spherical coordinate question on Phi

    Quote Originally Posted by lc99 View Post
    I've tried [0,2pi] as an answer but it's incorrect.
    Did you try $[0,2\pi)$?
    Thanks from topsquark and lc99
    Follow Math Help Forum on Facebook and Google+

  5. #5
    Member
    Joined
    Sep 2017
    From
    nj
    Posts
    196
    Thanks
    1

    Re: Help with spherical coordinate question on Phi

    Still not correct unfortunately. And ran out of tries. I typed [0,2pi) with the pi symbol exactly. It seems right. Perhaps the notation?
    Follow Math Help Forum on Facebook and Google+

  6. #6
    Member Walagaster's Avatar
    Joined
    Apr 2018
    From
    Tempe, AZ
    Posts
    130
    Thanks
    62

    Re: Help with spherical coordinate question on Phi

    I think you are all looking at the wrong angle. $\phi$ measures the angle from the $z$ axis to the surface. It is $\theta$ that goes from $0$ to $2\pi$ (the usual polar coordinate angle). You can tell that from the equation $r = g(\theta,z)$. For $\phi$ you have to go between the asymptotes. I would try $\phi \in (\frac \pi 4,\frac {3\pi} 4)$.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Geographical location using Spherical Coordinate system
    Posted in the Differential Geometry Forum
    Replies: 2
    Last Post: May 13th 2012, 02:08 AM
  2. Triple integral (spherical coordinate)
    Posted in the Calculus Forum
    Replies: 1
    Last Post: Jul 8th 2011, 09:47 AM
  3. Replies: 1
    Last Post: Jul 4th 2011, 01:16 AM
  4. Replies: 6
    Last Post: Jun 11th 2011, 11:15 AM
  5. Spherical Coordinate problem
    Posted in the Calculus Forum
    Replies: 1
    Last Post: May 3rd 2010, 02:17 PM

/mathhelpforum @mathhelpforum