V
,
, PROBLEMV6.1
UsingV theV methodV ofV joints,V determineV theV forceV inV eachV memberV o
fV theVtrussVshown.VStateVwhetherVeachVmemberVisVinVtensionVorVcompr
ession.
SOLUTION
FreeVbody:VEntireV tru
ss:
FyV =V ByV =V BVyV =
0: 0 0
−VBxV(16Vin.)V−V(240V lb)(36V in
M =V .)V=V0
BxV =V −540V kN BVxV =V540Vlb
FxV =V
0: CV −V540V lbV+V240V lbV=V0
CV =V300Vlb CV=V300Vlb
FreeVbody:VJointV
B:
FABV FBCV 54
=V =V
05
Vlb 4 3
CopyrightV©VMcGraw-
HillVEducation.VPermissionVrequiredVforVreproductionVorVdisplay.
, PROBLEMV6.1V(Continue
d)
FreeVbody:VJointV
C:
FACV FBCV 30
=V =V
013
Vlb 12 5
FBCV =V720VlbV V (che
cks)
CopyrightV©VMcGraw-
HillVEducation.VPermissionVrequiredVforVreproductionVorVdisplay.