Please look at this pic for the problem. http://thumb5.webshots.com/t/57/757/4/82/60/2732482600078932085VPLQzD_th.jpg(adsbygoogle = window.adsbygoogle || []).push({});

I have drawn the freebody diagrams correctly.

http://thumb5.webshots.com/t/53/453/3/64/60/2611364600078932085NMvdfG_th.jpg

http://thumb5.webshots.com/t/53/453/3/64/60/2611364600078932085NMvdfG_th.jpg

I solved for F' to be 14.07 N, but I cant solve Fr. I think the key to the problem is the law of sines. According to autocad the angle opposite Fr is 13 degrees, but how do I solve for that myself without autocad?

Here's some work ive done:

90-20=70 degrees

F’2=(50 N)2 + (20 N)2 -2(50 N)(20 N)cos(70)

F’=47.07 N

47.07 N 50 N

----------= -------- Θ=86.46 degrees

Sin 70 sin Θ

90-86.46= 23.53 degrees

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# Homework Help: Force vectors

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