Extrapolating the Quality factor for decay in amplitudes

AI Thread Summary
The discussion revolves around calculating the decay of amplitude over time and its relationship to the quality factor (Q) in oscillatory systems. The user initially determines the time interval as t=QT but questions the correctness of their approach, particularly regarding the interpretation of one cycle as T=2π. They seek clarification on how a decay factor of 2 in amplitude affects stored energy, suggesting a misunderstanding of the relationship between amplitude and energy. The conversation hints that a decay in amplitude does not equate to a simple halving of stored energy, indicating a need for deeper analysis. Overall, the thread emphasizes the importance of accurately connecting amplitude decay to energy changes in oscillatory systems.
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Homework Statement


By what factor does the amplitude decay in the time interval (which I had to find).

E: stored energy
γ:damping rate
a: amplitude
t: time
Q: quality factor
T:Period
ω: frequency

Homework Equations



Q = 2∏E/(ΔE)

The Attempt at a Solution


I found the interval to be t=QT
but "one cycle" indicates T=2∏?

So I'm not exactly sure if I got the right answer for the quality factor by which the quality factor decays? I feel like there is supposed to be a numerical answer. Any insights? Did I mess up anywhere or took the wrong approach? Anything will help!

Thanks!
 

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Suppose the amplitude decays by a factor of 2 in a certain interval. What does that mean for the stored energy ?

Vice versa yields your answer without much effort !

[edit] In fact your answer can be made to look more attractive if you realize that ##\omega T = 2\pi## :smile:
 
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BvU said:
Suppose the amplitude decays by a factor of 2 in a certain interval. What does that mean for the stored energy ?

Vice versa yields your answer without much effort !

[edit] In fact your answer can be made to look more attractive if you realize that ##\omega T = 2\pi## :smile:
It would lose half of it's stored energy?
 
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Nope.
 
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