Question

A sensitive computer is being transported by rail in a box car. Acelerometer measurements indicate that when the train is traveling at its normal speed of 85 m/s the dominant

component of the box car's vertical acceleration is 8.5 m/s² at a frequency of 5.73 Hz. The crate in which the computer is being transported is being tied to the floor of the boxcar. What is the required stiffness of the isolator with a damping ratio of 0.5 such that the acceleration amplitude of the60 kg computer is less than 0.5 m/s2? With this isolator, what is the displacement of the computer relative to the crate?

Fig: 1