Q3. Two bars of rectangular cross section (thickness t=15 mm) are connected by a bolt in the manner shown in the figure. The allowable shear stress in the bolt is 90 MPa and the allowable bearing stress between the bolt and the bars is 150 MPa. If the tensile load P =31 kN, what is the minimum required diameter dmin of the bolt? P -------

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A horizontal load P is applied to an assembly consisting of two inclined bars, as shown in the figure.  The cross-sectional area of bar (1) is 1.30 in.2, and the cross-sectional area of bar (2) is 1.75 in.2.  The normal stress in either bar may not exceed 24 ksi.  Determine the maximum load P that may be applied to this assembly.  Assume dimensions of a=14.5 ft, b=9.0 ft, and c=14.5 ft.  Determine the allowable force F1 in member (1) and the allowable force F2 in member (2).

Axial loads are applied with rigid bearing plates to the solid cylindrical rods shown in the figure.  One load of P=33P=33 kipskips is applied to the assembly at A, two loads of Q=30Q=30 kipskips are applied at B, and two loads of R=35R=35 kipskips are applied at C.  The normal stress magnitude in aluminum rod (1) must be limited to 1717 ksiksi.  The normal stress magnitude in steel rod (2) must be limited to 3030 ksiksi.  The normal stress magnitude in brass rod (3) must be limited to 2121 ksiksi.  Determine the minimum diameter required for each of the three rods.

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