At the beginning of each term, a physics professor named Dr. Zeus shows the class his expectations of them through a demonstration that he calls “Lesson #1.” He stands at the center of a turntable that can rotate without friction. He then takes a 2-kg globe of the earth and swings it around his head at the end of a 0.8-m chain. The world revolves around him every 3 s, and the professor and the platform have a moment of inertia of 0.5 kg ∙ m2.

(a) What is the angular speed of the professor?

(b) What is the total kinetic energy of the globe, professor, and platform?