Задача 40188.

Determine the mass of a body that performs harmonic oscillations with amplitude A = 0.1 m, frequency v = 2 Hz and initial phase 30 degrees, if the total energy of oscillations is E = 7.7 mJ. After how many seconds from the origin of time, the kinetic energy will be equal to the potential energy.

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