Finding the total response of an undamped spring mass system

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whitejac
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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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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.