1. Mass moment of inertia The assembly is made of the slender rods that have a mass per unit length of 3 kg/m. Determine the mass moment of inertia of the assembly about an axis perpendicular to the page and passing through point O. 2. Kinetics: Force and torque. Equation of motion The 4-kg slender rod is initially supported horizontally by a spring at B and pin at A. Determine the angular acceleration of the rod and the acceleration of the rod's mass center at the instant the 100-N force is applied. 3. Work and energy: Use principle of work and energy The 10-kg uniform slender rod is suspended at rest when the force of F150 N is applied to its end. Determine the angular velocity of the rod when it has rotated 90 clockwise from the position shown. The force is always perpendicular to the rod. 3 m 0.4 m 0.4 m 0.8 m 100 N 1.5 m + 1.5 m B A k = 20 N/m