A solid stainless steel [G = 12,500 ksi] shaft that is 30 in. long will be subjected to a pure torque of T = 565 lb-in. Determine the minimum diameter D required if the shear stress must not exceed 8,000 psi and the angle of twist must not exceed 0.050 rad. O 0.937 in. O 0.725 in. O 0.466 in. O 0.858 in. O 0.669 in.

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A hollow steel [G = 12,000 ksi] shaft with an outside diameter of 3.50 in. will be subjected to a pure torque of T = 4420 lb-ft. Determine the maximum inside diameter d that can be used if the shear stress must not exceed 8,000 psi and the angle of twist must not exceed 3° in an 8-ft length of shaft. O 3.07 in. O 2.38 in. O 2.75 in. O 2.52 in. O 1.50 in.

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