Question

An applied stress fluctuates between 2.79 kpsi and 4.18 kpsi. What's the midpoint stress?

A. 3.485 kpsi

B. 1.4 kpsi

C. 4.875 kpsi

D. 1.39 kpsi

12. A steel beam is repeatedly loaded from 580 MPa to 840 MPa. The stress intensity modification factor is 0.89 and the width of the initial crack is a = 1.3 mm. What's the change in the stress intensity factor in this beam?

A. 518 MPa · √m

B. 391 MPa · √m

C. 410 MPa · √m

D. 505 MPa · √m

Answer 1