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Homework Help: Density and mass

  1. Jun 16, 2008 #1
    1. The problem statement, all variables and given/known data
    A cylinder C1 has density D1, and C2 has density 2D1. The height of C1 is 3 times as large as height of C2, and the radius of C2 is 4 times as large as the radius of C1. Find the ratio of the mass of C1 to C2.

    2. Relevant equations
    Volume of Cylinder=(pi) R^2(L)

    3. The attempt at a solution
    Volume of C1=(pi)R^2(3H)
    Volume of C2=(pi)(4R)^2(H)

    Mass of 1= D1(pi)(R)^2(3H)
    Mass of 2=2D1(pi)(4R)^2(H)

    SO mass of C1 to C2 would be {D1(pi)(R)^2(3H)}/{2D1(pi)(4R)^2(H)}

    Answer I came up with was 3/32. Is this right???
  2. jcsd
  3. Jun 16, 2008 #2


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    Homework Helper

    Hi student_1,

    Your method looks right to me. Is there something about it that doesn't seem right to you?
  4. Jun 16, 2008 #3
    I got an answer totally different the first time just seeing if i was doing it right. I believe I had the wrong method at first though.
  5. Jun 17, 2008 #4
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