How Do Oscillator Configurations Affect Energy and Damping?

razor108
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Homework Statement


problemuy7.jpg


For a mass m hung vertically from a spring with spring constant s, the restoring Force is F=-sx where x is the displacement from equilibrium.

a)What are the periods of the two harmonic oscillators i) and ii).
b)Assuming eaqch oscillator is moving with the same Amplitude A which has the greater total energy of oscillation and by what factor is it greater?

Homework Equations



F=-sx
omega=(s/m)^1/2


The Attempt at a Solution



I just don't really know if there is any difference between i) and ii) but there has to be since all the following questions build up on it. But how can I prove that mathematically?
 
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The first thing you need to do is figure out the effective spring constant of those two spring configurations. Analyze how the force depends on the displacement: F = k' x.
 
Yes, I got it now.
The series one adds as in series therefore 1/stotal=1/s1+1/s2 and the other one like parallel therefore stotal=s1+s2.
Wouldn't have thought this because experience actually told me that it shouldn't be so much of a difference... I mean ii) has 4 times more total energy than i).

But now I'm stuck at a new problem.

A damped oscillator of mass m=1,6 kg and spring constant s=20N/m
has a damped frequency omega' htat is 99% of the undamped frequency omega.

a) What is the damping constant r?
Attempt:
As far as I know \omega ' = \sqrt{ \omega ^2 - \frac{b}{2m}}
But were to go from here?
edith: Ok, got that now.

therefore b = (0.99^2-1)*(s/m)*(2m)*(-1) which in this case is 0.796.

b)What is the Q of the system?
Attempt:
Q=\sqrt{mass * Spring constant} / r
But again I would have to find r from a) which I can't really figure out.
Ok, with a) answered I got Q to beeing 7.1066

c) Confirm that the system is lightly damped.
I think a system is lightly damped if omega' is about euqal to omega, but this can't really be the answer here. Because that's what's stated anyways since 99% is "about equal" isn't it?

d) What new damping constant r_{new} is required to make the system critically damped?
Again, I couldn't find any definition on the web or in my notes what critically damped means.

f)Using r_{new} calculate the displacement at t=1s given that the displacement is zero and the velocity is 5 ms^-1 at t=0.
No clue here.

Note:How can I insert Tex in this forum?
 
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To solve this, I first used the units to work out that a= m* a/m, i.e. t=z/λ. This would allow you to determine the time duration within an interval section by section and then add this to the previous ones to obtain the age of the respective layer. However, this would require a constant thickness per year for each interval. However, since this is most likely not the case, my next consideration was that the age must be the integral of a 1/λ(z) function, which I cannot model.
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