Question

The (304 stainless steel) hollow drive shaft (shown schematically below) provides power from the engine to the propeller of a large cruise ship. The shaft has an outside diameter of 7.0 inches and-an inside diameter of 6.2 inches. The engine produces 3,000 horsepower (hp) at 250 revolutions per minute (rpm). The thrust created by the propeller provides a compressive force in the shaft of 25,000 pounds (lb), which may be assumed to be uniformly distributed over the shaft's cross section. The yield stress for 304 stainless steel is 30 ksi in both compression and tension. a) What is the shear stress at the outside of the shaft that is created by the engine? b) Use Mohr's circle to determine if the shaft yields according to the maximum normal stress theory?

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