Is -16kN*m Equivalent to 16kN*m CW?

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SUMMARY

The discussion centers on the interpretation of moment signs in mechanics, specifically whether -16kN*m is equivalent to 16kN*m clockwise (CW). The user questions the sign convention, noting that a clockwise moment typically indicates a negative value according to the right-hand rule. However, the solution manual states the moment as 16kN*m CW without a negative sign, leading to confusion. The consensus is that while -16kN*m and 16kN*m CW represent the same physical moment, the sign convention can vary based on context.

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  • Familiarity with the right-hand rule for determining moment direction.
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  • Study the right-hand rule in detail to clarify moment direction conventions.
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This discussion is beneficial for students in mechanical engineering, physics enthusiasts, and professionals dealing with static mechanics and structural analysis.

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The 10kN force is applied at point A. Determine the moment of F about point O.


I attached the image. I have a question regarding the sign. The direction of rotation is clockwise, wouldn't that mean the moment is (-)? The right-hand rule also points your thumb into the page which means it's negative. The book&solution manual, however, is saying that it is 16kN*m CW. Is the "CW" (clockwise) basically means you don't have to put the (-) sign? I'm confused. Does -16kN*m=16kN*m CW?
 

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pyroknife said:
The 10kN force is applied at point A. Determine the moment of F about point O.


I attached the image. I have a question regarding the sign. The direction of rotation is clockwise, wouldn't that mean the moment is (-)? The right-hand rule also points your thumb into the page which means it's negative. The book&solution manual, however, is saying that it is 16kN*m CW. Is the "CW" (clockwise) basically means you don't have to put the (-) sign? I'm confused. Does -16kN*m=16kN*m CW?

It is the samething as going 20MPH west equals going -20MPH east.
 

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