Trouble Understanding Moment Calculations?

AI Thread Summary
The discussion revolves around confusion regarding moment calculations and the signs associated with them. The user initially believes that a 600 N force acting on a moment arm produces a clockwise (CW) moment, which would yield a negative value. However, upon further reflection, they realize that the force actually generates a counterclockwise (CCW) moment, leading to a positive value. This misunderstanding resulted in swapped Ay and Cy values compared to the book's solution. The user expresses gratitude for the clarification received during the discussion.
Permanence
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Hi,

I am having trouble understanding how the signs were obtained in the moment calculation.

When I imagine the 600 N force acting on the moment arm, it moves CW which would give it a negative value. When I solve the problem I end up reviving Ay and Cy values that are swapped with the book.
 
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Permanence said:
When I imagine the 600 N force acting on the moment arm, it moves CW which would give it a negative value.
The 600N force is to the right, that's counter clockwise about point C.
 
I thought that I'm suppose to draw a line down from C to the line of action of the force. Then apply the force to that line, and imagine (ignore that)

As I'm writing my response I see that it is CCW. I have no idea why I thought it was CW and was so insistent upon that. Thank you for the reply.
 
You're welcome :smile:
 
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