Suppose that a very simple ballistic pendulum is made by attaching a 25 kg cubical wooden block 0.36 m on each side to a 1.5 m long thin metal rod with a mass of 2.5 kg. The rod is attached to the block in the center of one of the faces. The assembled pendulum (rod plus block) is hung straight down from a smooth axle so that the block is at the bottom. The pendulum can rotate freely about the axle. A 4.0 g bullet moving perfectly horizontally (and perpendicular to the axle) at 920 m/s strikes the block in the center of one of the faces. The bullet embeds itself in the exact center of the block. What is the angular speed of the entire system about the axle after the collision?