The rotating shaft shown in the figure is machined from AISI 1040 CD steel (s = 490 MPa, Sut

590 MPa). It is subjected to a traverse force of F = 8 kN between the supports. The system designed to

be operated at a temperature of 120°C with a reliability of 99%. Estimate the number of cycles. All

dimensions are in mm. Assume all fillets are 3mm in radius.