Shear Force Diagram: 45N at 0.6m from B vs. 0.5m from D - Homework Question

Click For Summary

Discussion Overview

The discussion revolves around the placement of a 45N force in a shear force diagram related to a homework question. Participants are examining the correct positioning of this force in relation to points B and D, and the implications for the shear force diagram.

Discussion Character

  • Homework-related
  • Debate/contested
  • Technical explanation

Main Points Raised

  • One participant questions why the 45N force is placed at D in the shear force diagram, suggesting it should be at 0.5m from D instead.
  • Another participant asserts that the 45N force is actually 0.6m from D and 0.9m from B, indicating a potential misunderstanding of the diagram's dimensions.
  • A later reply clarifies that the 45N force is indeed acting at 0.6m from D, but questions the diagram's representation, suggesting that the graph should reflect a downward force at point E instead of D.
  • One participant proposes drawing a free-body diagram of the handle at D to analyze the forces and moments required for equilibrium, emphasizing the need for equal and opposite reactions on the beam.
  • Another participant reiterates the concern about the force's placement, arguing that the graph should reflect the force acting at E, not D, while referencing similar issues discussed in another thread.

Areas of Agreement / Disagreement

Participants express differing views on the correct placement of the 45N force in the shear force diagram, with no consensus reached on whether it should be at D or E. The discussion remains unresolved regarding the implications of these placements.

Contextual Notes

There are unresolved assumptions regarding the dimensions and points of application of forces in the shear force diagram, as well as the implications for equilibrium conditions.

chetzread
Messages
798
Reaction score
1

Homework Statement


In this question , the 45N is acting at 0.6m from B ...
why the author put the 45N forces at D in the shear force diagram ? Is it wrong ?

Homework Equations

The Attempt at a Solution


IMO , the 45N should be put at 0.5m from D . Correct me if i am wrong
 

Attachments

  • IMG_20161018_110628.jpg
    IMG_20161018_110628.jpg
    22 KB · Views: 435
Physics news on Phys.org
chetzread said:
In this question , the 45N is acting at 0.6m from B .
Looks to me that it is 0.6m from D and 0.9m from B.
 
haruspex said:
Looks to me that it is 0.6m from D and 0.9m from B.
sorry , i mean the 45N is acting at 0.6m from D .
Why , in the diagram , the author' bring down' the graph by 45kN at point D ? the graph should go down by 45kN at E ( which is 0.6m from D ) , right ?
 
It may help to draw a free-body diagram of just the "handle" attached at D. For equilibrium to be satisfied in the handle, what is the force and moment required to act on the handle at the point where it connects to the beam? Once you determine this, recall that equal and opposite reactions must act on the beam from the handle.
 
chetzread said:
sorry , i mean the 45N is acting at 0.6m from D .
Why , in the diagram , the author' bring down' the graph by 45kN at point D ? the graph should go down by 45kN at E ( which is 0.6m from D ) , right ?
Same issue as in the other thread. The beam feels the forces and moments at the point of attachment, D.
 
  • Like
Likes   Reactions: chetzread

Similar threads

Engineering Calculating shear center for a "skewed" I beam
  • · Replies 1 ·
Replies
1
Views
2K
Correct Shear Force and Bending Moment Diagrams for Beam Analysis
  • · Replies 1 ·
Replies
1
Views
2K
Shear force diagram and bending moment diagram
  • · Replies 10 ·
Replies
10
Views
3K
Engineering Calculate shear force and bending moments with a UDL and a point load
  • · Replies 2 ·
Replies
2
Views
5K
Shear force in influence line of beam
  • · Replies 2 ·
Replies
2
Views
2K
Shearing Force Direction and Sign Convention
  • · Replies 4 ·
Replies
4
Views
2K
Why Is the Larger Shear Force Value Used in Beam Stress Calculations?
  • · Replies 3 ·
Replies
3
Views
2K
Shear force and bending moment
  • · Replies 16 ·
Replies
16
Views
4K
Shear force for minimum links is greater than the maximum sh
  • · Replies 1 ·
Replies
1
Views
1K
Shear and Moment Diagram Equations
  • · Replies 2 ·
Replies
2
Views
2K