A horizontal spring is lying on a frictionless surface. One end of the spring is attached to a wall whle the other end is connected to a movable object. The spring and object are compressed by 0.064 m, released from rest, and subsequently oscillate back and forth with an angular frequency of 11.5 rad/s. What is the speed of the object at the instant when the spring is stretched by 0.037 m relative to its unstrained length? ... I tried using KEo + PEo + SPEo = KEf + PEf + SPEf ... but, I can't get anywhere ... ... I found out that the frequency is 18.05hz and it's relative time is .056 seconds - and that's where I'm stuck!