Moments question help requested, unsure where I went wrong

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Homework Help Overview

The discussion revolves around a problem related to moments, specifically focusing on the application of forces and significant figures in calculations. Participants are examining the assumptions made regarding the location of forces and the implications of rounding in their answers.

Discussion Character

  • Conceptual clarification, Assumption checking

Approaches and Questions Raised

  • Participants discuss the significance of rounding in their calculations and question the assumptions about where the forces act on the bridge. There is an exploration of how these factors might affect the final answers.

Discussion Status

Some participants have acknowledged potential errors related to significant figures and the placement of forces, indicating a productive exchange of ideas. There is a recognition of overlooked details in the problem statement, but no explicit consensus has been reached.

Contextual Notes

There is mention of data being given to only 2 significant figures, which may influence the answers. Additionally, the problem specifies where the forces are assumed to act, which is under consideration in the discussion.

TheePhysicsStudent
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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
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The Answer
 
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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.
 
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Ah, thank you yep, I believe it is an SF error, Thanks again for the help everyone!
 
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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.
 

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