4.19 A circular disk with radius r rotates in a horizontal plane about a fixed vertical axis O. A bar has mass m and length 2v2r. It is in P happily articulated at the circular disk. A pin on the circular disc at B protrudes from the smooth notch of the bar G and causes the bar and the circular disc to move as a single body. Point B coincides with the mass center G of the bar. Determine the normal force from the pin on the bar, if the angular velocity is w and the angular acceleration a. You have to draw the free body diagram and kinematic diagram of the figure. The answaer of the question is V2 N = mr 2