Share 'mech. pro. 1.3

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Engineering Mechanics (Statics) 
 66 
Problems (1-3) 
22) The members of a truss are pin connected at joint O. 
Determine the magnitudes of F1 and F2 for equilibrium. 
Set θ = 60o. 
 
Prob. 1.22 
23) If the bucket weighs 50 lb, determine the tension 
developed in each of the wires. 
 
Prob. 1.23/24 
Chapter 1 Vectors 
 
66 
24) Determine the maximum weight of the bucket that 
the wire system can support so that no single wire develops 
a tension exceeding 100 lb. 
25) Determine the stretch in springs AC and AB for 
equilibrium of the 2-kg block. The springs are shown in the 
equilibrium position. 
 
Prob. 1.25/26 
26) The unstretched length of spring AB is 3 m. If the 
block is held in the equilibrium position shown, determine 
the mass of the block at D. 
27) Determine the magnitude and direction θ of the 
equilibrium force exerted along link FAB by the tractive 
apparatus shown. The suspended mass is 10 kg. Neglect the 
size of the pulley at A. 
Engineering Mechanics (Statics) 
 66 
 
Prob. 1.27 
28) Consider the 75-kg crate shown in figure. This crate was 
lying between two buildings, and it is now being lifted onto a 
truck, which will remove it. The crate is supported by a 
vertical cable, which is joined at A to two ropes which pass 
over pulleys attached to the buildings at B and C. It is desired 
to determine the tension in each of the ropes AB and AC. 
29) A sailor is being rescued using a boatswain’s chair that is 
suspended from a pulley that can roll freely on the support 
cable ACB and is pulled at a constant speed by cable CD. 
Knowing that α = 30o and β = 10o and that the combined 
weight of the boatswain’s chair and the sailor is 900 N, 
determine the tension (a) in the support cable ACB, (b) in the 
traction cable CD. 
 
Chapter 1 Vectors 
 
66 
 
Prob. 1.28 
 
 
Prob. 1.29 
30) Determine the tension developed in each wire used to 
support the 50-kg chandelier. 
31) If the tension developed in each of the four wires is not 
allowed to exceed 500 N, determine the maximum mass of the 
chandelier that can be supported. 
Engineering Mechanics (Statics) 
 67 
 
Prob. 1.30/31 
32) The ball D has a mass of 20 kg. If a force of F = 100 N 
is applied horizontally to the ring at A, determine the 
dimension d so that the force in cable AC is zero. 
 
Prob. 1.30/31 
End.