Meriam, Kraige & Bolton — Plane Kinetics of Rigid Bodies: Problem 6_133

6/133 The aerial tower shown is designed to elevate a workman in a vertical direction. An internal mechanism at B maintains the angle between AB and BC at twice the angle $\theta$ between BC and the ground. If the combined mass of the man and the cab is 200 kg and if all other masses are neglected, determine the torque $M$ applied to BC at C and the torque $M_B$ in the joint at B required to give the cab an initial vertical acceleration of $1.2 \text{ m/s}^2$ when it is started from rest in the position $\theta = 30^\circ$.