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Homework Help: Surface of enclosed volume

  1. Jan 28, 2007 #1
    1. The problem statement, all variables and given/known data
    Hi,
    I have this problem:
    the surfaces r=2 and 4, [math]\theta=[/math]30 degrees and 50 degrees, [math]\phi=[/math]20 degrees and 60 degrees identify a closed surface.
    1- find the enclosed volume.
    2- Find the total area of the enclosed surface. ( I think it is a typo from the teacher. It is volume not surface)

    The first question is straigth forward
    For the secon question I have some issues.



    2. Relevant equations
    Do I need to take take each element of surface (in spherical coordinates)
    dS1=[tex]r^2[/tex] sin(theta) [tex]d\theta[/tex] [tex]d\phi[/tex]

    dS2=[tex]r[/tex]*[tex]dr[/tex][tex]d\phi[/tex]
    dS3=[tex]\sin\theta[/tex]*[tex]r[/tex][tex]dr[/tex][tex]d\phi[/tex]



    3. The attempt at a solution

    integrate the according the limits and the total are should be
    S= S1+S2+S3
    Is my reasonnig correct?
    Thank you
    B
    1. The problem statement, all variables and given/known data



    2. Relevant equations



    3. The attempt at a solution
    1. The problem statement, all variables and given/known data



    2. Relevant equations



    3. The attempt at a solution
    1. The problem statement, all variables and given/known data



    2. Relevant equations



    3. The attempt at a solution
    1. The problem statement, all variables and given/known data



    2. Relevant equations



    3. The attempt at a solution
     
    Last edited: Jan 28, 2007
  2. jcsd
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