Platform as a horizontal disc rotatable about a vertical axis passing through the center of the platform. On the platform there is a person, whose condition can be considered as a material point objectives. Energy consumption to overcome the frictional forces negligible. Man sitting on a stationary platform and holding above the head end of the cord to the other end of which is attached a weight of 2 kg. Find the period, which will rotate the platform with a person if the person will lead to rotate with the load, which, by making 1 revolution per second, will describe a horizontal circle with a radius of 2 m. The moment of inertia of the platform with a man of 10 kg * m2. Massa cord and friction forces neglected.

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