If VA = 77.7 2 in/sec in the figure below, find w, the angular speed of bar B. A B, 8 in. of -10 in. 12 in. By To calculate the angular speeds of the two bars B and B3, you need to use the two point formula: 1) first on rigid body B to calculate the velocity of point B (since you know velocity at point A) 2) then on rigid body B3 to calculate the velocity of point D (since you know velocity at point B) 3) Note that the velocity at point D has to be zero. Thus the two components of the velocity are zero giving you two equations to solve for the two unknown angular velocities. Figure is from "Engineering Mechanic An Introduction to Dynamics", McGill and King.