Problem 1Four gears are attached to a circularshaft and transmit the torques shown in the �gure. The allowable shear stress in the shaft is 10,000 psi. (a) What is the required diameter d of the shaft if it has a solid cross section? R// d=1.78 in(b) What is the required outside diameter d if the shaft is hollow with an inside diameter of 1.0 in.? R// d=1.83 in

Problem 2A motor delivers 275 hp at 1000 rpm to the end of a shaft (see �gure). The gears at B and C take out 125 and 150 hp, respectively. Determine the required diameter d of the shaft if the allowable shear stress is 7500 psi and the angle of twist between the motor and gear C is limited to 1.5°. (Assume G = 11.5E6 psi, L1 = 6 ft, and L2 = 4 ft.) R// d=2.75 in

Problem 3The composite shaft shown in the �gure is manufactured by shrink-�tting a steel sleeve over a brass core so that the two parts act as a single solid bar in torsion. The outer diameters of the two parts are d1 _ 40 mm for the brass core and d2 _ 50 mm for the steel sleeve. The shear moduli of elasticity are Gb _ 36 GPa for the brass and Gs _ 80 GPa for the steel. Assuming that the allowable shear stresses in the brass and steel are tb _ 48 MPa and ts _ 80 MPa, respectively, determine the maximum permissible torque Tmax that maybe applied to the shaft. R// T=1520 Nm