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!

Derivation of formula of centroid

  1. Nov 23, 2015 #1
    1. The problem statement, all variables and given/known data
    what is y ′and y bar ? why y ′ is changed to y bar ? why are they = 0 ?

    2. Relevant equations


    3. The attempt at a solution
     

    Attached Files:

  2. jcsd
  3. Nov 23, 2015 #2
    The middle integral is zero because y' is measured w.r.t. to the centroid so that
    each value of y' dA is cancelled by -y' dA by definition of a centroid or in other
    words y-bar = zero when measured from the centroid.
    Also, since y' is measured from the centroid then the integral of y'^2 dA is just
    the moment of inertia about the center of mass which is Ix.
     
  4. Nov 23, 2015 #3
    in the first integral , the
    in the first integral , the y prime is squared , so they dont cancel out each other?
     
  5. Nov 23, 2015 #4

    SteamKing

    User Avatar
    Staff Emeritus
    Science Advisor
    Homework Helper

    When have you squared a real number and it came out negative?
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted



Similar Discussions: Derivation of formula of centroid
  1. Formula Derivation (Replies: 2)

  2. Deriving Formulae (Replies: 2)

  3. Deriving Formulas (Replies: 1)

  4. Derivation of Formulas (Replies: 17)

  5. Deriving A Formula (Replies: 3)

Loading...