The 1-kg bar is held in the position shown in figure QB3, where the spring is unstretched. Note that the spring attached to its end always remains vertical due to the roller guide at C. 1 kg 2 m Figure QB3 (adapted from Hibbeler) 10 N/m (a) When the bar is released from rest in this position, it falls down clockwise and eventually stabilise at an angle 8o. calculate to using the moment equation at equilibrium. [5 marks] (b) Using the Work-Energy principle, calculate the angular speed @ of the bar AB when it has fallen clockwise, making an angle of 10 with the horizontal. [15 marks]