A flat bar of width b= 60 mm and thickness t is loaded in tension by a force P (see figure). The bar is attached to a support by a pin of diameter d= 20 mm that passes through a hole of the same size in the bar, The allowable tensile stress on the net cross section of the bar is 140 MPa, and the allowable shear stress in the pin is 75 MPa. Side View Top View The maximum force P that the pin can withstand is equal to

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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.