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!

Spherical vs cylindrical notation

  1. Mar 30, 2015 #1
    1. The problem statement, all variables and given/known data
    Plotting a point in spherical coordinates means using the format ##(\rho, \theta, \phi)## in place of ##(x, y, z)##. Taking a triple integral means replacing ##dV## with ##\rho ^2 sin(\phi) d\rho d\theta d\phi ## As you can see, ##\rho, \theta, \phi ## are all in the same order.

    However, for cylindrical coordinates, my textbook plots ##(r, \theta, z)## for points, but replaces ##dV## with ##r dz dr d\theta ##. Why are the three integrals suddenly switched around?


    2. Relevant equations
    n/a

    3. The attempt at a solution
    Is there a reason behind this? I dislike rote memorization
     
  2. jcsd
  3. Mar 30, 2015 #2

    blue_leaf77

    User Avatar
    Science Advisor
    Homework Helper

    Nothing to worry about, ##dV## is an elemental volume with the shape of a "box". You won't care how you are going to arrange the order of the formula for the volume of a box, will you.
     
    Last edited: Mar 30, 2015
  4. Mar 30, 2015 #3

    Mark44

    Staff: Mentor

    I mostly agree with blue_leaf77 -- the order of integration doesn't really matter. The "box" is a rectangular paralellipiped in cartesian coordinates, but in cylindrical or spherical coordinates, the ends aren't flat, and the "box" tapers toward the small end.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted



Similar Discussions: Spherical vs cylindrical notation
Loading...