A man stands at the center of the bench Zhukovsky and keeps at arm's length weight weight of 5 kg. Distance between garyami 1.3 m. Symmetrical compression arms distance from the axis of rotation weights decreased to 15 cm, the rotational speed of the bench changed. The moment of inertia and weights bench with a man on it at arm's length to 10 kg * m ^ 2. Determine how to change the rotation speed of the bench, knowing that at the first position dumbbell bench rotated at 120 min ^ -1. What kind of work will make people change the position of weights?

Detailed solution shorthand terms, formulas and laws used in the decision, the withdrawal of the calculation formula and the response.
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