The energy magnitude is proportional to:
"E \\propto \\exp\\left(-\\frac{1}{Q}\\omega t\\right)"
where "\\omega = 2\\pi\\times 300s^{-1} = 600\\pi"
Let "t_1" be the initial moment of time and "t_2" be the final one. Thus, the ratio of energies (which is eventually equal to 1/10) is:
"\\dfrac{E_{final}}{E_{initial}} = \\dfrac{ \\exp\\left(-\\frac{1}{Q}\\omega t_2\\right)}{ \\exp\\left(-\\frac{1}{Q}\\omega t_1\\right)} = \\exp\\left(-\\frac{1}{Q}\\omega (t_2-t_1)\\right) = \\\\\n= \\exp\\left(-\\frac{1}{Q}\\omega \\Delta t\\right) = \\dfrac{1}{10}" where "\\Delta t" is an required time interval. Expressing "\\Delta t" from the last equation, get:
"\\Delta t = \\dfrac{Q\\ln10}{\\omega} = \\dfrac{5\\times 10^4\\cdot 2.3}{600\\pi} \\approx 602.14s" Answer. 602.14 s.
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