A grievance has been filed by the union at Dorben Co. regarding the final inspection station, in which the operator slightly lifts a 20 lb assembly, examines all sides, and, if acceptable, sets it back down on the conveyor, where the assembly goes to the packing station. The inspector examines, on average, 5 assemblies per minute at an energy expenditure level of 6 kcal/min. The conveyor is 40 inches off the floor and the assembly while being inspected is roughly 20 inches from the inspector. Evaluate the job with respect to the NIOSH lifting guidelines and metabolic energy expenditure considerations. Indicate whether the job exceeds allowable limits. If it does, calculate how many assemblies the inspector may inspect per minute without exceeding acceptable guidelines.

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?