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!

Spherically symmetric

  1. Mar 11, 2017 #1
    1. The problem statement, all variables and given/known data
    Hi guys, having problem trying to understand what this question wants.

    upload_2017-3-11_23-50-0.png
    the question I am stuck with is 7.3.
    2. Relevant equations


    3. The attempt at a solution
    So for a) I converted to spherical co-ordinates:
    ##log(r^2sin^\theta cos^2\phi+r^2sin^2\theta sin^2\phi+r^2 cos^2\theta)## which simplifies to ##log(r^2)=2log(r)##
    is this correct?

    for b) I am not quite sure what it wants. Could someone please advise. Thanks in advance
     
  2. jcsd
  3. Mar 11, 2017 #2

    blue_leaf77

    User Avatar
    Science Advisor
    Homework Helper

    You forgot the 1 inside the log argument.
    You can try calculating its gradient ##\nabla f(r)## and then the directional derivative in an arbitrary direction perpendicular to the radial unit vector ##\hat r##.
     
  4. Mar 11, 2017 #3

    LCKurtz

    User Avatar
    Science Advisor
    Homework Helper
    Gold Member

    @Taylor_1989 : What is your definition of a function being spherically symmetric?
     
  5. Mar 12, 2017 #4
    @LCKurtz Well looking at the above function, wid the 1 in. It will have to go from the center of the axis because the way i see it each side about the center will have the same volume, but if you say move it to the left one side will have a larger volume that the other.
     
  6. Mar 12, 2017 #5

    LCKurtz

    User Avatar
    Science Advisor
    Homework Helper
    Gold Member

    You were asked to show a certain function is spherically symmetric. How can you expect to do that if you don't know what being spherically symmetric is? That should have been included in the homework template under "relevant equations", which you left blank. Look in your text, find the definition, and quote it here. Then we might be able to help you.
     
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: Spherically symmetric
  1. Symmetric tensor (Replies: 1)

  2. Symmetric Polynomial (Replies: 2)

  3. Symmetric Equation (Replies: 1)

  4. Symmetric Group (Replies: 28)

Loading...