A loaded railroad car weighing 30.000 lb is rolling at a constant velocity v0when it coupl...

A loaded railroad car weighing 30.000 lb is rolling at a constant velocity v0when it couples with a spring and dashpot bumper system (Fig. 1). The recorded displacement-time curve of the loaded railroad car after coupling is as shown (Fig. 2). Determine (a) the damping constant, (b) the spring constant. (Hint:Use the definition of logarithmic decrement given in 19.129.)