Question

The joint of a space frame is subjected to four member forces. Member OA lies in the x-y plane and member OB lies in the y-z plan. Determine the force F3 required for equilibrium of the joint. See figure for reference. Click Save and Submit to save and submit. Click Save all Answers to save all answers.

Answer 1

$\vec F_1 = F_1\cos 30 \hat j - F_1\sin 30 \hat i$

$\vec F_2 = F_2\cos 35 \hat j - F_2\sin 35 \hat k$

$\vec F_3 = -F_3 \hat k$

$\vec F_4 = +200 \hat j$

$\vec F_{net} = \vec F_1 + \vec F_2 + \vec F_3 + \vec F_4$

$\vec F_{net} =(F_1 \cos 30 + F_2\cos 35 + 200) j -F_1 \sin 30 \hat i - (F_3 +F_2\sin 35) \hat k = 0$

$F_1 \sin 30 \hat i = 0 \hat i$

$F_2 \cos 35 + 0 +200 = 0$

$F_3 + F_2\sin 35 = 0$

$F_3= 244.15 \sin 35$