Задача 10904.

The CD, which can rotate around a vertical axis washer is a mass of 100 g is connected to a spring washer from the drive shaft. If the number of revolutions of the disk is less than 2 V / s, the spring is undeformed. If the number of turns of 5 / s, the spring is extended by half. Determine spring stiffness.

Detailed recording solution formulas and the laws used in the decision, the withdrawal of the formula.
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