(Solved): The 4-1b collar is released from rest at A and slides down along the smooth rod as shown in (Figure ...

The 4-1b collar is released from rest at $A$ and slides down along the smooth rod as shown in (Figure 1). Figure 1 of 1 If the attached spring has a stiffness $5\mathrm{lb}/\mathrm{ft}$. determine its unstretched length so that it does not allow the collar to leave contact with the top surface of the rod until $\theta =60^{\circ }$. Express your answer in feet to three significant figures. \& Incorrect; Try Again; 5 attempts remaining