A 20-lb weight is suspended from the end of a vertical string having a spring constant of 40 lb/ft and is allowed to reach equilibrium. It is then set into motion by stretching the spring 2 in from its equilibrium position and releasing the mass from rest. Find the position of the weight at any time t if there is no external force and no air resistance.

Question

anonymous · Answer

|dw:1386225012642:dw|
at time t > 0, there will be no external forces acting on a weight m=20 lb.