3.10 Draw the physical model and free-body diagram of a C clamp (Figure P3.9).
Figure P3.9 C clamp.
4.10 The boat tows three water skiers. The skier A makes an angle of 300 with the direction of the
boat ride, while the skier B makes an angle of 50. The skier C makes a negative angle of 250.
Assume that the forces that are acting on each skier are 200 lb. Calculate the magnitude of the
resultant force acting on the boat and its angle relative to the direction of the boat ride.
M6.12(222) Determine the forces in the pole AB and cables AC and AD that support two electrical
wires. The wires are perpendicular one to another, are in the horizontal plane and each one is under
the tension T. Angle CBD = 900.
A
90°
D
60°
60°
C
B
D
C
A
ϕ 90°
5.23 (M3.23) The railroad crane mounted on the cart is riding along the tracks as shown. Weight of
the cart applied at A is 30 kN, weight of the crane applied at C is 10kN, weight of the counter
balance D is 20kN, weight of the link FG applied at H is 5kN. Determine the largest load Q that can
be safely hoisted by the crane.
Fig. P5.23
M4.20 A crane (weight P = 120 kN) is lifting a load G = 200 kN. Determine the reactions at the
supports A and D and tension in the link BD. AB = AD = BD = 8 m.
y
B
8m
D
P
A
5m
G
x
15m
6.5 Find the center of gravity of an object bounded by a parabola y = 4 x 2 and a line y = x (Figure
P6.5)
Figure P6.5
311(d). Locate the centroid of the homogeneous wire.
y
a
120°
a
x
Ja12.23
φ5
z
30
14
20
15
y
50
15
O
35
10
x
8.43 B.33 In the system shown the member BC is in horizontal direction. When load P is
applied at the joint B what will be the force in each member? Angles α and β are given.
Α
D
α
Β
β
C
β
P
E
8.79 Determine the force in each member of the truss. What are the reaction forces at A and B?
P1 = 2 kN, P2 = P3 = 4 kN, P4 = 6 kN, P5 = P6 = 2 kN, α = 30o.
a
P1
a
a
a
P2
a
P3
B
a
1,2a
1,5a
A
a
P5
P4
8.? – 8.? Determine forces in each truss member , when P = 3 kN, Q = 2 kN, a = 20 cm, b =40cm
and c = 50 cm. Force P is always acting along the line AB and force Q along the line DE.
b
a
3
B
P
A
2
1
c
4
6
5
E
D
Q
9.9 Draw the diagrams of internal moments and forces in the
shelf supporting the stacks of CDs.
b) The weight of each stack is 5 lb and the weight of the
short stack is 1 lb. Assume that the width of each stack is 6 in.
and the space between the stacks is 6 in. as well. The space
between the long and short stack is 1 in.
Figure P9.4 Shelf with compact disks stacks
Use an intuitive approach (do not write equations for each region)
179. The homogeneous bar AB (weight 3 kN) leans on the support E. The homogeneous bar CD
(weight 6 kN) is loaded by weight M = 1.2 kN. CB = 3 m, BD = 1m, BE = 0.707 m. The angle
ACB = 450 . Determine the reactions at A, C and E.
y
C
E α
A
B
x
D
P
B38. The press is activated by the rotation of the link OA. At the moment shown, the force P is
applied on the B. Determine the force acting on the body M, when α = 600 and β = 300.
B
P A
β
O
α
D
C
M
Ja4.22
P1
45°
M1
M2
A
C
B
2.0
P2
q
2.5
2.0
D
2.5
F
E
3.5
2.0
1.5
Ja2.13
60
o
D
M0 q
C
F
60
o
2a
2a a a
G
C A E
2a
E
4.35 M4.3 The ball M (weight Q and radius a) and the weight P are suspended by the cables as
shown. Determine the angle φ when the system is in equilibrium. Use OM = b.
O
ϕ
a
M
P
B78. What is the load acting on the barrel at D, if a = 100 cm, b = 10 cm and M = 300 kN.
a
A
C
B
b
D
M
B1. The mass M1 (weight P) is supported by rod and is held in position shown by weight M2.
Determine weight M2 and tension in the rod.
Ο
α
M1
Α
M2
159. Cube A is placed in the horizontal plane while cylinder B is placed on the inclined plane.
Weight of cube A is QA and weight of a cube B is QB. Assuming there is no friction between
the elements determine the force acting from cylinder to cube and from cylinder on plane.
Determine minimum weight of cube A that will keep the system in equilibrium.
B
A
α
C