8. Horizontal platform mass m = 25 kg, and a radius R = 0.8 m rotates at n1 = 18 min-1. In the center stands a man and holding in the hands of the weight arranged. Assuming platform disk, determine the speed of the platform, if a man, his arms, reduce its moment of inertia of the J1 = 3,5 kg • m 2 to J2 = 1 kg • m2.

Detailed solution. Decorated in Microsoft Word 2003. (Target decided to use formula editor)