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Homework Help: Related Rates; Sphere

  1. Nov 7, 2013 #1


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    Gold Member

    1. The problem statement, all variables and given/known data

    http://i.minus.com/jbxIzu0P7sTqP0.png [Broken]

    2. Relevant equations

    V(sphere) = 4/3(pi)(r^3)

    V = 36pi in^3

    dr = -0.2 in

    dV = ?

    3. The attempt at a solution

    I basically solved for the radius, and took the derivative and plugged in the value of the radius and the change in the radius to get the change in the volume.

    http://i.minus.com/jbsA5BJkMOPHgl.jpg [Broken]

    Also upon further consideration it appears that one can easily eliminate the answers that claim the volume increases since that wouldn't make any geometric sense; if the radius was shrinking one would naturally expect the volume of a sphere to follow suit.
    Last edited by a moderator: May 6, 2017
  2. jcsd
  3. Nov 7, 2013 #2


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    Homework Helper

    I see no question here.
  4. Nov 7, 2013 #3


    Staff: Mentor

    Looks good!
    Last edited by a moderator: May 6, 2017
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