1. Not finding help here? Sign up for a free 30min 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!

Young's modulus

  1. Dec 10, 2005 #1
    hi i was wondering if i did this correctly.

    Q: A wire 2.5m long has a cross-sectional area of 2.5 mm^2. It is hung vertically and a 4.5 kg mass is hungfrom it. Byhow much does the wire stretch if Young's modulus for that material is 2.0 x 10^11 N/m^2 ?

    so i did Y = ( F / A ) / ( del L / L )

    2.0 x 10 ^ 11 N/m^2 = (( 4.5 kg * 9.81 m / s^2 ) / (0.0025 m^2)) / ( del L / 2.5 )

    delta L = ((4.5 kg)(9.81 m/s^2)(2.5m))/((.0025m^2)(2x10^11 N / m^2))
    = 2.21 x 10 ^ -7 meters
     
  2. jcsd
  3. Dec 10, 2005 #2

    Dale

    Staff: Mentor

    You set it up correctly. Assuming your arithemetic is right you got it.

    -Dale
     
  4. Dec 10, 2005 #3

    Fermat

    User Avatar
    Homework Helper

    1 mm = 10^(-3) m
    1 mm² = 10^(-6) m²
    2.5 mm² = 2.5*10^(-6) m²

    Apart from that, your working is fine. Just multiply your answer by 1000.
     
  5. Dec 10, 2005 #4

    Dale

    Staff: Mentor

    Oops, I missed that. Quite correct Fermat.

    -Dale
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: Young's modulus
  1. Young Modulus (Replies: 2)

  2. Youngs modulus (Replies: 5)

Loading...