Physics
posted by Erick .
A horizontal spring is lying on a frictionless surface. One end of the spring is attaches to a wall while the other end is connected to a movable object. The spring and object are compressed by 0.076 m, released from rest, and subsequently oscillate back and forth with an angular frequency of 17.8 rad/s. What is the speed of the object at the instant when the spring is stretched by 0.045 m relative to its unstrained length?

x=Asinωt
v=dx/dt =Aω cosωt= Aω•sqrt(1sin²ωt) =
=ω•sqrt(A²  A² sin²ωt)= ω•sqrt(A² x²)
A=0.076 m
x= 0.045 m
ω =17.8 rad/s
v= ω•sqrt(A² x²)= …