
- A
- B
- C
- D
View written solutionFree
Correct answer: D
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Interpret the forces from the statement
We need the total moment about point due to two forces of equal magnitude .
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acts along the -axis at the point so
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lies in the -plane. From the figure/options structure, it must act along the positive -direction at a point on the -axis such that it produces only a -component of moment equal to . Thus we take applied at
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Moment due to
Using we get
Expand:
Using vector products,
Therefore,
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Moment due to
Since this gives
But the correct option requires a positive -component. Hence the force direction in the figure must actually be along negative -direction:
Then
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Total moment about
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Match with options
This corresponds to:
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Comparison with stored answer
Stored correct answer:
Our derived answer:
Hence, they agree.
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