j
,
, PROBLEMj6.1
Usingj thej methodj ofj joints,j determinej thej forcej inj eachj memberj ofj thejtruss
jshown.jStatejwhetherjeachjmemberjisjinjtensionjorjcompression.
SOLUTION
Freejbody:jEntirej truss:
Fyj =j0: Byj =j0 Bjyj =j0
MCj =j 0: −jBxj(16jin.)j−j(240j lb)(36j in.)j=j0
Bxj =j −540j kN Bjxj =j540jlb
Fxj =j0: Cj −j540j lbj+j240j lbj=j0
Cj =j300jlb Cj=j300jlb
Freejbody:jJointjB:
FABj FBCj 540jlb
=j =j
5 4 3
Copyrightj©jMcGraw-HilljEducation.jPermissionjrequiredjforjreproductionjorjdisplay.
, PROBLEMj6.1j(Continued)
Freejbody:jJointjC:
FACj FBCj 300jlb
=j =j
13 12 5
FBCj =j720jlbj j (checks)
Copyrightj©jMcGraw-HilljEducation.jPermissionjrequiredjforjreproductionjorjdisplay.