Moments question help requested, unsure where I went wrong

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The discussion centers on a question regarding the calculation of forces in a bridge problem. Participants highlight the importance of rounding answers to two significant figures, as some data is provided in that format. There is clarification that the support forces should be considered acting at the bridge's meeting points with the supports, rather than at the edges. Acknowledgment of a significant figure error is noted, leading to a consensus on the rounding approach. Overall, the conversation emphasizes careful attention to problem details and rounding conventions in physics calculations.
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
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The Question
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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):

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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.
 
Ah, thank you yep, I believe it is an SF error, Thanks again for the help everyone!
 
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.
 
Beams of electrons and protons move parallel to each other in the same direction. They ______. a. attract each other. b. repel each other. c. neither attract nor repel. d. the force of attraction or repulsion depends upon the speed of the beams. This is a previous-year-question of CBSE Board 2023. The answer key marks (b) as the right option. I want to know why we are ignoring Coulomb's force?