Equation for simple harmonic motion

AI Thread Summary
The discussion centers on finding a specific equation for simple harmonic motion (SHM) that begins with a particular format involving exponential decay and sine functions. The original poster is seeking this equation for an assignment due soon. Responses indicate that the equation likely represents a case of damped oscillations rather than standard SHM equations, which typically include cosine and sine functions without exponential decay. Participants emphasize the need for additional details, such as the original differential equation and initial conditions, to accurately identify or reproduce the requested solution. The conversation highlights the importance of understanding the context and parameters of the problem to derive the correct equation.
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i was just wondering if anybody knew where i could find the equation for simple harmonic motion (SHM). I have found loads but not the right one. i need the one that starts... y=e(^-3wnt)*Asin(wdt)+(Asin(wt)/SQRT(l-(w^2/wn^2)^2+... anyone got any ideas? got assignment to hand into uni tomorrow and i need it bad :biggrin:
 
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:confused: I never saw any equation for SHM that starts like that. The ones I know are:
x(t) = A\cos (\omega t + \phi)
v(t) = -A\omega \sin (\omega t + \phi)
a(t) = -A\omega ^2 \cos (\omega t + \phi)
 
I looks to me like you have a specific solution to a specific problem. It appears to be a case of damped ossiliations, but in no way is it an equation that you will find on the web. If you could post the specifics of the problem it is a solution to we may be able to help you. We need the original DE and the initial conditions.
 
its an equation for the vibration of a ball on a spring, i am comparing my excel model to the one i made on a program called working drawing.
 
The equation you posted is the solution to a Differential Equation with initial values. Without this information, I do not see how we can reproduce the solution. What are the initial conditions, what is the damping function. (your solution is damped) Is there a driving function? Without these details we cannot reproduce the solution.
 
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I have recently been really interested in the derivation of Hamiltons Principle. On my research I found that with the term ##m \cdot \frac{d}{dt} (\frac{dr}{dt} \cdot \delta r) = 0## (1) one may derivate ##\delta \int (T - V) dt = 0## (2). The derivation itself I understood quiet good, but what I don't understand is where the equation (1) came from, because in my research it was just given and not derived from anywhere. Does anybody know where (1) comes from or why from it the...
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