If there is no friction between shaft AB and the collar, what angular velocity 0 must the mechanism have to keep the collar at r = 960 mm from the vertical axis? Express your answer to three significant figures. Learning Goal: To set up and analyze equations of motion in a cylindrical View Available Hint(s) coordinate system. The mechanism shown in the figure below rotates about the vertical axis. The collar has mass m = 3.3 kg. The spring AEQ It vec Be ? has an unstretched length of 665 mm and the spring constant is k = 250 N/m. The distance d = 400 mm , and the collar is required to stay a fixed distance r = 960 mm 0 = rad /s from the vertical axis. (Figure 1) Submit Request Answer Part B - The minimum required angular velocity when there is friction Consider the same mechanism again, with m = 3.3 kg, d = 400 mm, k = 250 N/m, only now, instead of being smooth, the collar and shaft have a maximum coefficient of friction of Us = 0.79. What is the minimum angular velocity required to keep the collar at a constant distance Figure