1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Problem with Conductivity

  1. Apr 17, 2007 #1
    1. The problem statement, all variables and given/known data

    A cylinder with a piston is filled with ideal gas. The gas temperature is held at 450 K. The cylinder is heated by an oven through a square metal rod connected between the oven and the cylinder. The rod has sides d = 1 cm and length L = 2.3 m.

    (a) If the oven is held at 750 K, and the heat current conducted through the metal rod is 27 W, find the thermal conductivity of the metal in the rod.

    k = W/m K
    9 NO

    HELP: H = k*A*(T2-T1) / L

    HELP: H is the heat current; k is thermal conductivity; T2 and T1 are temperatures at two ends; A and L are cross-sectional area and length of the rod.

    2. Relevant equations

    H = k*A*(T2-T1) / L

    3. The attempt at a solution



    I'm pretty sure im right here... the following quesion asks,

    For a larger cylinder at 450 K, a heat current of 57 W is needed. If we use the same metal rod to conduct heat, find the oven temperature in Kelvin that will maintain the necessary heat current.

    and i used the k value 9 and gave me an answer 1083.3, which was the correct answer...
  2. jcsd
  3. Apr 18, 2007 #2
    looks right.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook