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Homework Help: Angular momentum NEED CLOSURE

  1. Oct 19, 2005 #1
    I have already got help with figuring this out. But i seem to be getting something wrong so maybe someone can check this over and tell me what im doing wrong

    Q) find the angular momentum of a cone with heigh H and radius R

    now i was helped and told

    Rc = int (x)dv / int dV where (x)dV is the volume element and int dV is the mass density

    now dV = pi (rx/h)^2 for a cone

    so i did angular momentum = int (r^2)dV / int dV

    where int (r^2)dV = pi int of (r^4 x^2 / h^2) dR
    = pi (r^5 X^2 / 5 h^2)


    mass density = pi ( r^3 x^2 / 3 h^2)

    so I = 3/5 r^2

    but im getting froma book I = 3/10 m r^2 for a cone

    please HELP!!!!!!

    tell me if u cant understand this
  2. jcsd
  3. Oct 19, 2005 #2


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