2.99 See Answer

Question: A brass wire of diameter d = 1/


A brass wire of diameter d = 1/16 in. is stretched between rigid supports with an initial tension T of 37 lb (see figure). Assume that the coefficient of thermal expansion is 10.6 × 10-6/°F and the modulus of elasticity is 15 × 106 psi.
(a) If the temperature is lowered by 60° F, what is the maximum shear stress τmax in the wire?
(b) If the allowable shear stress is 10,000 psi, what is the maximum permissible temperature drop?
(c) At what temperature change ∆T does the wire go slack?


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> Solve the preceding problem for the following data: b = 8.0 in., k = 16 lb/in., a = 458, and P = 10 lb. Data from Problem 20: A framework ABC consists of two rigid bars AB and BC, each having a length b (see the first part of the figure part a). The ba

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> An aluminum wire having a diameter d = 1/10 in and length L = 12 ft is subjected to a tensile load P (see figure). The aluminum has a modulus of elasticity E = 10,600 ksi If the maximum permissible elongation of the wire is 1/8 in. and the allowable stre

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> A compression bar having a square cross section with sides 50 b 5 mm is subjected to load P. The bar is constructed from two pieces of wood that are connected by a glued joint along plane pq that is inclined at angle α = 35°. The

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> A tension member is to be constructed of two pieces of plastic glued along plane pq (see figure). For purposes of cutting and gluing, the angle u must be between 25° and 45°. The allowable stresses on the glued joint in tension and

> The normal stress on plane pq of a prismatic bar in tension (see figure) is found to be 7500 psi. On plane rs, which makes an angle β = 30° with plane pq, the stress is found to be 2500 psi. Determine the maximum normal stress &Ium

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> A prismatic bar with a length L = 3 ft and cross-sectional area A = 8 in2 is compressed by an axial centroidal load P = 10 kips. Determine the complete state of stress acting on an inclined section pq that is cut through the bar at an angle Î&cedil

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> During a tension test of a mild-steel specimen (see figure), the extensometer shows an elongation of 0.00120 in. with a gage length of 2 in. Assume that the steel is stressed below the proportional limit and that the modulus of elasticity E = 30 Ã

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> Rigid bar ACB is supported by an elastic circular strut DC having an outer diameter of 15 in. and inner diameter of 14.4 in. The strut is made of steel with a modulus elasticity of E = 29,000 ksi. Point load P = 5 kips is applied at B. Calculate the chan

> By what distance h does the cage shown in the figure move downward when the weight W is placed inside it? (See the figure.) Consider only the effects of the stretching of the cable, which has axial rigidity EA = 10,700 kN. The pulley at A has a diameter

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> A steel cable with a nominal diameter of 25 mm is used in a construction yard to lift a bridge section weighing 38 kN, as shown in the figure. The cable has an effective modulus of elasticity E = 140 GPa. (a) If the cable is 14 m long, how much will it s

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> A 10-ft rigid bar AB is supported with a vertical translational spring at A and a pin at B. The bar is subjected to a linearly varying distributed load with maximum intensity qo. Calculate the vertical deformation of the spring if the spring constant is

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> Find expressions for all support reaction forces in the plane frame with load 2P applied at C, as shown in the figure. Joint A is a sliding support, joint D is pinned, and joint F is a roller support. Assume that member AC is a flat prismatic bar of leng

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> A horizontal rigid bar of weight W = 7200 lb is supported by three slender circular rods that are equally spaced (see figure). The two outer rods are made of aluminum (E1 = 10 × 106 psi)with diameter d1 = 0.4 in and length L1 = 40 in. The in

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> The aluminum and steel pipes shown in the figure are fastened to rigid supports at ends A and B and to a rigid plate C at their junction. The aluminum pipe is twice as long as the steel pipe. Two equal and symmetrically placed loads P act on the plate at

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> Two cables, each carrying a tensile force P = 1200 lb, are bolted to a block of steel (see figure). The block has thickness t = 1 in and width b = 3 in. (a) If the diameter d of the cable is 0.25 in., what are the maximum tensile and compressive stresses

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> The bar ABC shown in the figure is loaded by a force P acting at end C and by a force Q acting at the midpoint B. The bar has a constant axial rigidity EA. (a) Determine the strain energy U1 of the bar when the force P acts alone (Q = 0). (b) Determine t

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> Repeat Problem 8, but assume that the bar is made of aluminum alloy and that BC is prismatic. Assume that P = 20 kips, L = 3 ft, t = 1/4 in, b1 = 2 in, b2 = 2.5 in., and E = 10,400 ksi. Data from Problem 8: Bar ABC is fixed at both ends (see figure) a

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2.99

See Answer