Moments question help requested, unsure where I went wrong

Click For Summary
SUMMARY

The discussion centers on the interpretation of forces acting on a bridge in a physics problem. Participants concluded that the support forces should be considered acting at the midpoint of the 1-meter width rather than at the edges. Additionally, they emphasized the importance of rounding answers to two significant figures due to the data provided. The consensus is that overlooking the location of the forces led to confusion in solving the problem.

PREREQUISITES
  • Understanding of significant figures in scientific calculations
  • Basic principles of static equilibrium in physics
  • Knowledge of force distribution in structural mechanics
  • Familiarity with bridge support systems
NEXT STEPS
  • Research the concept of significant figures in physics problems
  • Study static equilibrium and its applications in engineering
  • Explore force distribution methods in structural analysis
  • Learn about bridge design principles and support mechanisms
USEFUL FOR

Students in physics or engineering courses, educators teaching mechanics, and professionals involved in structural analysis and bridge design.

TheePhysicsStudent
Messages
21
Reaction score
17
Homework Statement
Hello! I was doing this question from a textbook and I am Unsure why my answer is slightly different to that of the textbook
Relevant Equations
M = Fd
SF1 + SF2 =SFT
1706720889229.png
The Question
1706720910104.png
What I did
1706720956273.png
The Answer
 
Physics news on Phys.org
Some of the data is given to only 2 significant figures. So, the answers might be rounded to 2 significant figures.

Also, the support forces at each end might be considered as acting in the middle of the 1-meter width rather than at the edge (dashed):

1706724571612.png
 
TSny said:
Also, the support forces at each end might be considered as acting in the middle of the 1-meter width rather than at the edge (dashed):
The problem states explicitly that the forces are assumed to act where the bridge meets the supports. I’d go with the rounding option.
 
Reply
  • Like
Likes   Reactions: TSny
Ah, thank you yep, I believe it is an SF error, Thanks again for the help everyone!
 
Reply
  • Like
Likes   Reactions: TSny
Orodruin said:
The problem states explicitly that the forces are assumed to act where the bridge meets the supports. I’d go with the rounding option.
Yes, I overlooked the comment about the location of the forces. Thanks.
 

Similar threads

General question about the definition of moment of force (Torque)
  • · Replies 7 ·
Replies
7
Views
916
Why are moments not included in free body diagrams?
  • · Replies 31 ·
2
Replies
31
Views
2K
Calculating Moment of Inertia for Hollow Cylinder w/ Water
  • · Replies 40 ·
2
Replies
40
Views
6K
Moment of inertia of a rectangular prism parallel to one face
  • · Replies 11 ·
Replies
11
Views
1K
Need Help with Physics Moment and Force Questions
  • · Replies 7 ·
Replies
7
Views
2K
Correct Use of the Parallel Axis Theorem for Moment of Inertia
  • · Replies 2 ·
Replies
2
Views
2K
Calculating Moments About a Point
  • · Replies 4 ·
Replies
4
Views
1K
Moment of inertia of a cuboid parallel to one of its faces (repost with diagram)
  • · Replies 25 ·
Replies
25
Views
2K
How do I find the intersection of the wrench's LOA?
  • · Replies 4 ·
Replies
4
Views
1K
Why do I have to take the moment at the cut to get the right answer?
  • · Replies 2 ·
Replies
2
Views
1K