A disk of $\backslash ($ r $\backslash )-$radius is rotating clockwise around the $\backslash ($ O $\backslash )$ point. The angular velocity $\backslash (\backslash$omega$\_\{0\}\backslash )$ of disk is constant. The link $\backslash ($ A B $\backslash )$ connects point $\backslash ($ A $\backslash )$ on the disk to point $\backslash ($ B $\backslash )$ on the collar. Knowing that collar can only move vertically, determine the angular acceleration of link $\backslash ($ A B $\backslash )$ and the acceleration of collar $\backslash ($ B $\backslash ).$