(Solved): The elements of the mechanism for deployment of a spacecraft magnetometer boom are shown. By the me ...

The elements of the mechanism for deployment of a spacecraft magnetometer boom are shown. By the method of this article, determine the angular velocity ${?}_{AC}$ (positive if counterclockwise, negative if clockwise) of the boom $AC$ when the driving link $OB$ crosses the $y$-axis with an angular velocity ${?}_{OB}=0.51\mathrm{rad}/\mathrm{s}$ if $\tan ?=6/5$ at this instant.