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Homework Help: Maximum eror in calculated surface area

  1. Mar 9, 2007 #1
    1. The problem statement, all variables and given/known data
    The circumference of a sphere was measured to be 73.000 cm with a possible error of 0.50000 cm. Use linear approximation to estimate the maximum error in the calculated surface area

    2. Relevant equations
    [tex]SA=4\pi\(r^2[/tex] Eq1.
    [tex]dV=8\pi\(rdr[/tex] Eq2.
    [tex]c=2\pi\(r[/tex] Eq3.

    3. The attempt at a solution
    I solved for the radius by [tex]r=\frac{73}{2\pi}[/tex]
    I then plugged r into Eq2, I set [tex]dr= \frac{.5}{2\pi}[/tex]
    I get something like 134.98 and it is wrong.
    Last edited: Mar 9, 2007
  2. jcsd
  3. Mar 9, 2007 #2
    Never mind, I figured it out.
  4. Mar 9, 2007 #3


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    Science Advisor
    Homework Helper

    You are calculating the error in the measured volume - not in the measured surface area.
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