Задача 10385.

What is the weight of the ball, rotating on a string around a vertical axis with the frequency n1 = 2 r / s, if a person, shortening the string with a 50 cm to 30 cm, has made the work of A = 0.36 J?

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