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: Poisson's Ratio Need Not Apply?

  1. Sep 22, 2008 #1
    A rubber block is subjected to an elongation of 0.03in along the x-axis, and its vertical faces are given a tilt so that theta=89.3deg. Find epsilonx, epsilony, and gammaxy. vr=0.5. The block is 4 in along the x-axis and 3 in along the y-axis.


    My solution

    epsilonx = 0.03/4 = .0075 in/in

    gammaxy = pi/2 - theta = pi/2 - 89.3(pi/180) = .0122 rad

    epsilony = - epsilonx/vr using Poisson's ratio = -.015 in/in
    HOWEVER
    The solutions states that

    epsilony = - epsilonx*vr = -.00375 in/in

    Why is this? This has been bugging me for three days
    1. The problem statement, all variables and given/known data



    2. Relevant equations



    3. The attempt at a solution
     
  2. jcsd
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Can you offer guidance or do you also need help?
Draft saved Draft deleted