CHAPTER 6
PROBLEM 6.1
Using the method of joints, determine the force in each member of the
truss shown. State whether each member is in tension or compression.
SOLUTION
PROBLEM 6.1 (Continued)
Free body: Joint C:
PROBLEM 6.2
Using the method of joints, determine the force in each member of the truss
shown. State whether each member is in tension or compression.
SOLUTION
Free body: Entire truss:
PROBLEM 6.2 (Continued)
Free body: Joint A:
PROBLEM 6.3
Using the method of joints, determine the force in each member of
the truss shown. State whether each member is in tension or
compression.
SOLUTION
Reactions:
0: 1260 lb
A
M C
0: 0
xx
F A
0: 960 lb
yy
F A
PROBLEM 6.4
Using the method of joints, determine the force in each
member of the truss shown. State whether each member is in
tension or compression.
SOLUTION
Reactions:
PROBLEM 6.4 (Continued)
15
0: ( 34.0) 0
17
xDE
FF  
30.0 kN
DE
F
30.0 kN
DE
FT
Joint E:
PROBLEM 6.5
Using the method of joints, determine the force in each
member of the truss shown. State whether each member is in
tension or compression.
SOLUTION
Reactions:
PROBLEM 6.5 (Continued)
Joint C:
1
0: 10 kips 0
5
yCA
FF  
22.4 kips
CA
F
22.4 kips
CA
FT
PROBLEM 6.6
Using the method of joints, determine the force in each member
of the truss shown. State whether each member is in tension or
compression.
SOLUTION
Reactions:
 
22
6 m 3.2 m 6.80 mDE  
PROBLEM 6.6 (Continued)
Joint D:

66
0: 51.0 kN 0
6.8 6.8
xBD
FF
 
 
 
 
51.0 kN
BD
FC
PROBLEM 6.7
Using the method of joints, determine the force in each
member of the truss shown. State whether each member is in
tension or compression.
SOLUTION
PROBLEM 6.7 (Continued)
Joint E:
54
0: 0
13 5
xBECE
FFF
  
(3)
12 3
0: 528 lb 0
13 5
yBECE
FFF  
(4)
Solving Eqs. (3) and (4) simultaneously,
832 lb
BE
F
832 lb
BE
FC
400 lb
CE
F
400 lb
CE
FT
PROBLEM 6.8
Using the method of joints, determine the force in each member of the truss
shown. State whether each member is in tension or compression.
SOLUTION
Free body: Entire truss:
0: 2(5 kN) 0
xx
FC 
10 kN 10 kN
x
x
C C

0: (2 m) (5 kN)(8 m) (5 kN)(4 m) 0
C
MD 
30 kN 30 kND D

PROBLEM 6.8 (Continued)
Free body: Joint C:
0: 10 kN 0
xCD
FF  
PROBLEM 6.9
Determine the force in each member of the truss shown. State whether
each member is in tension or compression.
SOLUTION
Reactions for Entire truss:
By inspection: 4 kN 4 kNAE
Free body: Joint A:
PROBLEM 6.9 (Continued)
Free body: Joint B:
0: 8cos30 cos30 cos30 0 (1)
xBCBG
FFF  

0 : 8sin 30 4 sin 30 sin 30 0 (2)
yBCBG
FFF  

Solving (1) and (2) simultaneously yields:
4.00 kN
BC
FC 
PROBLEM 6.10
Determine the force in each member of the truss shown. State whether each
member is in tension or compression.
SOLUTION
Free body: Entire truss:
0: 0
xx
F F