Problem 4. Consider the half section of a pipe of mass m and radius r as depicted in Fig. 4 where C denotes the center of curvature and G denotes the center of mass. The distance GC is given by 2r/ . After the pipe is released from rest in the position shown, it is rolling without slipping. Any friction in this problem is supposed to be small enough to be neglected. a) Employ the parallel axis theorem to determine the mass moment of inertia of the pipe associated with its center of mass G. b) Use the result found in Part a) and employ the principle of conservation of energy to determine the angular velocity @ of the pipe after it has rolled through 90. c) Use the result found in Part b) to determine the normal reaction force N under the pipe at the same instant. Figure 4: A half section of a pipe before rolling without slipping.