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Homework Help: Determining Maximum bending moment via shear force diagram

  1. Oct 5, 2008 #1
    1. The problem statement, all variables and given/known data

    http://imagebin.ca/img/uzuDsi.jpg [Broken]

    and by maximum it means in magnitude

    2. Relevant equations

    I figured the best (easiest/quickest) method would be to draw the shear force diagram.

    When I originally did this problem I came up with equations for M and V by dividing the bar into sections from the right until the last section in which I took the section from the right to include the external moment for the M equation. I am not sure how to figure out V for the last section though.


    V=
    0<x<2 V=40-10x V facing down and M going counterclockwise
    2<x<5 V= -5 V facing down and M going counterclockwise
    5<x<7 V= -15 V facing down and M going counterclockwise
    7<x<10 V=-10 facing up and M going counterclockwise
    The part I am not sure about is how the external moment of 35 comes into play in the last section.

    I feel like it would be incorrect to say V = 10 for the last section?


    What would the final shear force plot look like?
    How do I finish this problem?
     
    Last edited by a moderator: May 3, 2017
  2. jcsd
  3. Oct 6, 2008 #2

    PhanthomJay

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    Your picture is not showing up. Be sure to determine external reactions first. When you plot a shear diagram, the diagram is unaffected by externally applied moments.
     
  4. Oct 6, 2008 #3

    tiny-tim

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    I found it … http://imagebin.ca/img/uzuDsi.jpg" [Broken]
     
    Last edited by a moderator: May 3, 2017
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