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: Thermal expansion

  1. Jun 4, 2006 #1
    a steel rod undergoes a streching force of 500n its crossectional area is 2cm^2 find the temp change that would elongate the rod by same amount
    i useyoungs modulus to get change in length so ym= (F/A)/(deltaX/h)
    so i solve for r (which is = to h from area of circle) and with a ym for steel of 20*10^10 i get delta X now i plug that into equation for linear
    which is deltaX = (average coeffiecent of linear expation for steel) = 11*10^-6 Linitial(which is what is giving me problems) *delta T (temp)
    i am not given the initial lenght how am i supposed to come up with it or substitute it for some other value??
  2. jcsd
  3. Jun 4, 2006 #2

    Andrew Mason

    User Avatar
    Science Advisor
    Homework Helper

    What is r? h should be the length of the rod. When you do the thermal expansion, the length drops out.

    Last edited: Jun 4, 2006
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook