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Homework Help: Cone Volume

  1. Jan 11, 2010 #1
    1. The problem statement, all variables and given/known data
    Find the volume, see attachment


    2. Relevant equations
    I can't find the proper equation for this cone.


    3. The attempt at a solution
    he triangle is a 3, 4, 5 triangle. Is the typical cone equation of 1/3*PI*r^2*h used or a different equation?
     

    Attached Files:

  2. jcsd
  3. Jan 11, 2010 #2
    Look at the units your equation would produce. If you used your equation you would get a unit that is squared implying a surface area such as meters squared (m^2). For a volume you need a unit that is cubed. So your equation is incorrect.

    Think of what you need to get the correct unit of volume.

    Thanks
    Matt
     
  4. Jan 11, 2010 #3
    The units would be m^3 (r*r*h)
     
  5. Jan 11, 2010 #4
    You got it.

    Now substitute the (r*r)*h into your equation from post 1 and you should get the correct answer.

    Sorry, I didn't catch the h in your first post. Looks you had it right all along.

    Thanks
    Matt
     
  6. Jan 11, 2010 #5
    So the regular cone equation can be used even though the cone is abnormal?
     
  7. Jan 11, 2010 #6
    Yes it can be.

    Thanks
    Matt
     
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