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Homework Statement
Points A and B are the midpoints of the sides of the rectangle. Replace the force F acting at A by a forcecouple system at B. Give the general result and then answer for the specific case: F = 250 N, h = 185 mm, b = 490 mm. The couple is positive if counterclockwise, negative if clockwise.
Homework Equations
The Attempt at a Solution
I found R to be:
R = 250cos(37.065) + 250sin(37.0565)
R = 199.51i + 160.651j
I know my R is correct but I can't get the M_{B} right.
If I draw a straight line connecting A and B, I find the angle at A in this triangle to be 20.6841 by using arctan.
At this point I have
M_{B} = 250N*261.88cos(36020.6841) + 250N*261.88sin(36020.6841)
M_{B} = 38.1249
It's negative because the force would clockwise. I've think I tried this answer previously and it was wrong. Does the y component go through the point B, thereby making it's value 0?
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