Bench Zhukovsky with a man standing in the middle of it, and leaning on the scrap length of 1.2 m and weighing 12 kg, is shown in rotation tension cord F = 20 N, acting in the course of t = 7 on the pulley R = 15 cm. The moment of inertia of the bench with the person J = 10 kg * m ^ 2. To determine the speed of the bench after a person raise the crowbar on the chest, turning it horizontally and holding the middle.

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