The horizontal platform 80 kg and 1 m radius rotates at 20 rev / min. At the center of the platform stands a man and holding weights in his hands arranged. What is the number of turns will make the platform, if a person, his arms, reduce its moment of inertia of 3 to 1 kg * m ^ 2? Consider a circular disk platform. How many times has increased the kinetic energy of platforms with a man?

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