Astrain gauge that has a nominal resistance of 350 w and a gauge factor of 1.8 is mounted in an equal-arm wheatstone bridge (equal-arm means that the other 3 resistors also have a 350 w resistance. these 3 resistors are not strain gauges). this strain gauge is mounted to sense axial strain. the bridge output voltage is 1 mv and the input voltage is 5 v. what is the axial strain measured by the strain gauge? if we also have strain in the transverse direction (perpendicular to the axial direction) and this strain is 15% of the axial one, what is the error in the previous axial strain due to a transverse sensitivity of the gauge of 0.05? the gauge factor of 1.8 was obtained from a tensile test on a steel specimen (poisson’s ratio = 0.27).

Tom is having a problem with his washing machine. he notices that the machine vibrates violently at a frequency of 1500 rpm due to an unknown rotating unbalance. the machine is mounted on 4 springs each having a stiffness of 10 kn/m. tom wishes to add an undamped vibration absorber attached by a spring under the machine the machine working frequency ranges between 800 rpm to 2000 rpm and its total mass while loaded is assumed to be 80 kg a) what should be the mass of the absorber added to the machine so that the natural frequency falls outside the working range? b) after a first trial of an absorber using a mass of 35 kg, the amplitude of the oscillation was found to be 10 cm. what is the value of the rotating unbalance? c) using me-3.5 kg.m, find the optimal absorber (by minimizing its mass). what would be the amplitude of the oscillation of the absorber?