Meriam, Kraige & Bolton — Plane Kinetics of Rigid Bodies: Problem 6_78

6/78 The robotic device consists of the stationary pedestal $OA$, arm $AB$ pivoted at $A$, and arm $BC$ pivoted at $B$. Member $AB$ is rotating about joint $A$ with a counterclockwise angular velocity of $2\text{ rad/s}$, and this rate is increasing at $4\text{ rad/s}^2$. Determine the moment $M_B$ exerted by arm $AB$ on arm $BC$ if joint $B$ is held in a locked condition. The mass of arm $BC$ is $4\text{ kg}$, and the arm may be treated as a uniform slender rod.