Solucionario De Hibbeler

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•3–1. Determine the force in each cord for equilibrium ofthe 200-kg crate. Cord BC remains horizontal due to the
roller at C, and AB has a length of 1.5 m. Set y = 0.75 m.

2m
A
y

C

1 21

B

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3–2. If the 1.5-m-long cord AB can withstand a maximum
force of 3500 N, determine the force in cord BC and the
distance y so that the 200-kg crate can be supported.

2m
A
y

C

1 22

B

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3–3. If the mass of the girder is 3 Mg and its center of mass
is located at point G, determine the tension developed in
cables AB, BC, and BD for equilibrium.

FAB
AB
45

30
D

C
G

1 23

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*3–4. If cables BD and BCcan withstand a maximum
tensile force of 20 kN, determine the maximum mass of the
girder that can be suspended from cable AB so that neither
cable will fail. The center of mass of the girder is located at
point G.

FAB
A
B
45

30
D

C
G

1 24

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•3–5. The members of a truss are connected to the gusset
plate. If the forces are concurrent at point O, determine the
magnitudes of F and T for equilibrium. Take u = 30°.
A

O

8 kN

u45
D
B
T

C

5 kN

F

3–6. The gusset plate is subjected to the forces of four
members. Determine the force in member B and its proper
orientation u for equilibrium. The forces are concurrent at
point O. Take F = 12 kN.

A

O

8 kN

u
45
D
B
T

C

F

1 25

5 kN

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3–7. The towing pendant AB is subjected to the force of
50 kN exerted by a tugboat. Determine the force in each of
the bridles, BC and BD, if the ship is movingforward with
constant velocity.

D

C
30

20

B

A
50 kN

1 26

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