Zero Amplitude Damped Simple Harmonic Motion with k=0.7s^-1 and f=3Hz

AI Thread Summary
The discussion revolves around understanding the concept of zero amplitude in damped simple harmonic motion, specifically with parameters k=0.7 s^-1 and f=3 Hz. Participants clarify that the amplitude, represented by e^-kt, never actually reaches zero, which can lead to confusion regarding the question posed. The focus shifts to determining the times t=0 and t=1 when the displacement x(t) equals zero, rather than the amplitude itself. This distinction is crucial for accurately addressing the problem. The conversation emphasizes the need for clarity in interpreting the question about displacement in the context of damped motion.
Timburton91
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Homework Statement
Damped Simple Harmonic Motion
Relevant Equations
x(t)=e^-kt cos(2πft)
Hi guys sorry if this is the wrong thread,
I have a damped simple harmonic motion pictured below, i have to find the inerval t=0 and t=1 for which the amplitude of x(t) is considered to be zero.

The behaviour of the graph below can be described as e^-kt cos(2πft)

k=0.7s^-1 and f= 3Hz
IMG_20200315_180120147.jpg
 
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I don't really understand the question, what makes more sense to me is to compute the values ##t_0## and ##t_1## that are the two smallest positive solutions to the equation $$x(t)=0$$ is this your question?
 
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Not really man, as, i guessed that would be zero.
Gaussian97 said:
I don't really understand the question, what makes more sense to me is to compute the values ##t_0## and ##t_1## that are the two smallest positive solutions to the equation $$x(t)=0$$ is this your question?
 
Timburton91 said:
Not really man, as, i guessed that would be zero.
What do you think the question is asking?
 
Timburton91 said:
Not really man, as, i guessed that would be zero.
Then, could you please explain to me what is exactly the question? I'm sorry, but I don't understand the question you post in #1.
 
The use of "amplitude " in the question may be misleading. In terms of the expression ##e^{-kt}\cos(2\pi ft)##, the amplitude is ##e^{-kt}##. This is never actually zero. I suggest the intended question is to find when the displacement x(t) is zero.
 
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