Archived Oscillation with Green's Function

AI Thread Summary
The discussion revolves around solving the motion of an oscillator subjected to an external force using Green's function. The force is defined as Fext(t) = F0[1 - e^(-αt)], and the parameters of the system include mass m, spring constant k, and damping force characterized by b = mq and k = 4mq². The solution involves integrating the Green's function to find x(t), resulting in a complex expression that the original poster struggles to simplify for the final position. There is a suggestion to balance the limiting force with Hook's law to determine the final position, as the Green's function method is deemed challenging for this problem. The thread highlights the difficulties in applying Green's function for this specific oscillator scenario.
Menteith
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Homework Statement


A force Fext(t) = F0[ 1−e(−αt) ] acts, for time t > 0, on an oscillator which is at rest at x=0 at time 0.
The mass is m; the spring constant is k; and the damping force is −b x′. The parameters satisfy these relations:
b = m q , k = 4 m q2 where q is a constant with units of inverse time.
Find the motion. Determine x(t); and hand in a qualitatively correct graph of x(t).
(B) Determine the final position.

Homework Equations


Green's Function:
x(t) = ∫-∞tF(t')G(t,t')dt'
where:
G(t,t') = (1/(m*ω1))*e-β(t-t')*sinω1(t-t') for t≥t'
= 0 for t<t'

The Attempt at a Solution


I have solved using green's function to obtain this mess:
(F0/m)*(e-βt/(β212))*((β/ω1)*sinω1t - cosω1t) - (F0/m)/((α-β)212)*[e-αt-e-βt*(cosω1t-((α-β)/ω1)sinω1t)]

From here, however, I am unsure of how to find the final position without the final time.
 
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The final position can be found by balancing the limiting force with Hook's law.
 
I would suggest you work the problem with a simple differential equation. The Green function approach for this one is rather difficult. If your instructor specified he requires a Green's function type solution, then it is the route you need to go, but for this one, the Green's function looks like a difficult approach. editing... I'm looking at the date on the OP. This one appears to be a couple of years old.
 
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