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Homework Help: Thermal Physics, finding the thermal conductivity of a metal

  1. Jan 28, 2013 #1
    1. The problem statement, all variables and given/known data

    One end of a metal rod is maintained at 100°C, and the other end is placed in a large
    container with ice and water at 0°C. The rod has length 50 cm and a cross-sectional area
    of 0.8 cm
    . The heat conducted by the rod melts 4 g of ice in 5 minutes. Calculate the
    thermal conductivity of the metal.

    2. Relevant equations

    Q=M*C*(Delta T)
    H=(-Delta T)/R
    R=(delta X)/KA
    3. The attempt at a solution
    The first thing that I did was find the heat of ice
    Q=(.4kg)(2050J/(M*K))(100-0) which gave me the value 82000 J
    Since I now know the heat I plugged this value into the H=(-Delta T)/R

    I solved and found that my R value was 1.2*E-3

    I manipulated the last equation to give me
    K=(delta x)/AR
    And found a K value of 1024.99

    I wanted to know if I did this problem correctly, any feedback would be appreciated
  2. jcsd
  3. Jan 28, 2013 #2


    User Avatar

    Staff: Mentor

    In calculating Q, the ice is melting (going from ice at 0C to water at 0C). No ΔT is involved.
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