Finding the total response of an undamped spring mass system

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The discussion focuses on finding the total response of an undamped spring-mass system using the equation x(t) = (x0 - (F0 / (k - mω²))cos(ωnt) + (x'/ωn)sin(ωnt) + (F0 / (k - mω²))cos(ωt). The natural frequency is calculated as ωn = √(k/m), yielding a value of 6.325 rad/s. The participants explore the possibility of solving for the applied force F0 and the exciting frequency ω, noting that these values are typically provided externally. Despite attempts to substitute functions for harmonic motion, the challenge remains due to having one equation with two unknowns. The discussion emphasizes the impact of gravity on the system's response under the given initial conditions.
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Homework Statement


spring mass system.JPG


Homework Equations


The response of a spring mass system can be simplified to equal:
x(t) = (x0 - (F0 / (k - mω2))cos(ωnt) + (x'/ωn)sin(ωnt) + (F0 / (k - mω2))cos(ωt)

where
x & x' are the initial conditions
ω is the exciting frequency
ωn is the natural frequency
k is the spring constant
m is the mass
and F0 is the amplification of the applied force

ωn = √(k/m)

The Attempt at a Solution


Given normal initial conditions, x = x' = 0

x(t) = - (F0 / (k - mω2))cos(ωnt) + (F0 / (k - mω2))cos(ωt)

and ωn = √(k/m) = 6.325rad / s
Is there a way to solve for F0 and ω?
 
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No. Those are arbitrarily supplied by an external agency.
 
Simon Bridge said:
No. Those are arbitrarily supplied by an external agency.
That's what I thought but someone said you could by substituting the given f (t) with the f (t) for harmonic motion - but it seemed like I still on had one one equation 2 unknowns so it didn't seem possible.
 
There are three terms in your "relevant equation". Which one or ones look like they could be affected by gravity alone? Remember initial conditions = 0.
 

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