1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Find volume of solid elliptic paraboloid using polar coordinates

  1. May 22, 2012 #1
    1. The problem statement, all variables and given/known data
    a elliptic paraboloid is x^2/a^2+y^2/b^2<=(h-z)/h, 0<=z<=h. Its apex occurs at the point (0,0,h). Suppose a>=b. Calculate the volume of that part of the paraboloid that lies above the disc x^2+y^2<=b^2.:confused:



    2. The attempt at a solution
    We normally do the questions that ask to find the volume of a cylinder. the polar coordinates are straight, which is x=rcos(), y=rsin();
    but in this question, i don't how to set up the polar coordinates for x and y..:frown:
     
  2. jcsd
  3. May 22, 2012 #2

    sharks

    User Avatar
    Gold Member

    Your equation for the elliptic paraboloid appears to be:
    [tex]\frac{x^2}{a^2}+\frac{y^2}{b^2}\le \frac{h-z}{h}[/tex]
    Make z the subject of the equation to get the upper limit, as z varies from z = 0. The rest should be easy enough, as you are expected to use cylindrical coordinates to describe the volume.
     
  4. May 22, 2012 #3
    thanks :)) sharks
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook