Question

A 3 kg mass (m) is attached to a stationary ceiling through a spring with stiffness ( K ) and damper. A force is

applied to create oscillating motion. This force is applied until time equals zero. After a short interval after time, a data recorder measures the mass’s position. This position data is plotted as a red line in the diagram below. Two of the maximum displacement positions are measured at 35 and 20 mm, respectively.

a) If the time interval between the +35 and the +22 mm displacements is 0.7 sec, determine the value of K.

b) Determine the unknown (??) displacement amplitude.

Mechanical Engineering