Задача 11088.

A skater weighing 70 kg begins to rotate at a frequency of 1 r / s, holding his hands horizontally. How often will it rotate if it raises its hands vertically? The skater´s body is considered to be a uniform cylinder of radius 15 cm, hands - 0.75 m rods and 5 kg each.

A detailed solution with a brief record of the condition, formulas and laws used in the solution, the derivation of the calculation formula and the answer.
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