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# Moment's question

1. Determine the moment of the 60N force about point A on the perimeter of the disk by determining the lever arm of the force:
(Note, the lever arm is the perpendicular distance from the line of action of the force to the point where the moment is to be taken about)

2. Any ideas?

I cannot calculate the perpendicular distance from the line of action of the force to the point A.
I have tried calculating the lengths of the other lines that would add up using pythagoras theorem to obtain the perpendicular, but I can't find the necessary angles.
3. (Original post by sulexk)
Any ideas?

I cannot calculate the perpendicular distance from the line of action of the force to the point A.
I have tried calculating the lengths of the other lines that would add up using pythagoras theorem to obtain the perpendicular, but I can't find the necessary angles.
Calculate AC by the cosine rule. The angle AOC is 165. AO=OC=250
The angle between AC and the force is 60 (75-15).
The perpendicular distance (d) d=AC*sin 60
4. (Original post by ztibor)
Calculate AC by the cosine rule. The angle AOC is 165. AO=OC=250
The angle between AC and the force is 60 (75-15).
The perpendicular distance (d) d=AC*sin 60
Thank you very much

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