a cylindrical 4340 steel bar is subjected to reversed rotating–bending stress cycling, which yielded the test results presented in animated figure 8.21. if the maximum applied load is 5,000 n, compute the minimum allowable bar diameter to ensure that fatigue failure will not occur. assume a factor of safety of 2.25 and that the distance between loadbearing points is 55.0 mm.

An engine, weighing 3000 n, is supported on a pedestal mount. it has been observed that the engine induces vibration into the surrounding area through its pedestal at the maximum operating speed. determine the stiffness of the dynamic vibration absorber spring in (n/m) that will reduce the vibration when mounted on the pedestal. the magnitude of the exciting force is 250 n, and the amplitude of motion of the auxiliary mass is to be limited to 2 mm note: in this question type-in right numbers, no decimals, no fractions, no unit. approximate to right number if needed