A mechanical engineer is testing the ultimate tensile for 42 specimens. The results obtained give a mean and variance of 420 MPa and 100 MPa, respectively. The 90% confidence interval for the ultimate tensile strength is most nearly:

Using the normal distribution graph show, identify the mean and the standard deviation:

A geotechnical engineering company can purchase a used drilling rig for $90,000 and spend $450 per day on operating costs. The drill rig will have a 5-year life with no salvage value. Alternatively, the company can lease a drill rig for $800 per day. How many days per year must the company use the leased drill rig in order to justify its purchase at an interest rate of 8% per year:

A layer of an unknown fluid contained between two horizontal parallel plates. The separation between the plates is 2.5 mm. The bottom plate is fixed while the upper plate moves horizontally at a velocity of 0.5 m/s when a horizontal force of 0.5 N is applied to it. The effective area of the upper plate in contact with the fluid is 0.15 m². The dynamic (absolute) viscosity of the fluid (N-s/m²) is most nearly:

A Mohr’s circle is shown for a point in a physical object that is subjected to plane stress. The angle \(2 \phi\) to the maximum principal stress plane is most nearly:

The cantilevered steel bar is subjected to a 100 kip point load as shown. The bar is bolted to a steel channel using four bolts. The primary and secondary shear forces, \(\left|\boldsymbol{F}_{1 i}\right|\) and \(\left|\boldsymbol{F}_{2 i}\right|\) are most nearly: