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Im going to be experimenting and I want top know what result I should get.

Position time graph of mass on spring B is damping coefficient in picture

This is basically what my graph is going to look like and it should help you get an idea of the experiment.

$$x(t)= x_0 e^{-\frac{c}{2m}}\cos (\omega t + \phi_0)$$

where c is damping coefficient

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closed as unclear what you're asking by Jon Custer, ZeroTheHero, Yashas, John Rennie, Kyle Kanos Mar 22 '17 at 10:18

Please clarify your specific problem or add additional details to highlight exactly what you need. As it's currently written, it’s hard to tell exactly what you're asking. See the How to Ask page for help clarifying this question. If this question can be reworded to fit the rules in the help center, please edit the question.

  • $\begingroup$ We'd get a better idea for the experiment if you showed the damping coefficient somewhere or you made it more obvious what you mean. As is your question is extremely vague. $\endgroup$ – JMac Mar 21 '17 at 15:56
  • $\begingroup$ @JMac this is basically all the background you need physics.stackexchange.com/questions/8495/… edit: ive forgotten how to use math jax sorry i added an equation $\endgroup$ – Adam apple Mar 21 '17 at 16:35
  • $\begingroup$ It depends on what they're modelling I guess. If it's an ideal damper then no, it should have a set coefficient. If it's a real system where we are just modelling some real behaviour as a dampening coefficient, the mass may affect it depending on how it interacts with the system. $\endgroup$ – JMac Mar 21 '17 at 16:39
  • $\begingroup$ It is usually under damping. So would damping coefficient decrease as mass increases @JMac $\endgroup$ – Adam apple Mar 21 '17 at 18:24
  • $\begingroup$ First, define which of your symbols is the "damping coefficient." I know what I think a damping coefficient is, but I don't have any reason to know if you think the same! (And there are plenty of real-world situations involving damping where your graph is not the response you would expect). $\endgroup$ – alephzero Mar 21 '17 at 18:35
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No, the damping coefficient will not vary with mass.

Based on the back in forth in the comments, you are confusing a few concepts here.

The damping coefficient (subscript $c$) is a measure of applied force compared to velocity. In terms of the equations of simple harmonic motion, this is a constant which has no terms dictated by mass.

Your mention of "under-damping" in the comments leads me to believe you are confusing damping coefficient $c$ with damping ratio $\zeta$.

$\zeta$ will determine the characteristics of the damped harmonic motion (i.e. under-damped, over-damped, critically damped). $\zeta$ is given by the equation $$\zeta = \frac{c}{2 \sqrt {mk}}$$ where $c$, $m$ and $k$ are all constants.

You can see that mass will absolutely affect the damping ratio, but not the damping coefficient (since that is assumed constant).

In a real life scenario the damper may not perform the same if different masses are used; but traditionally with the idealized equations it just has a constant value.

I find the Wikipedia page has some good information on harmonic oscillation. Also, if I misunderstood what your question was really about please let me know.

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  • $\begingroup$ I was originally talking about damping coefficient but as it is not dependent on mass and wont change i can look at how mass affects the damping ratio. MANY THANKS! im sorry about being vague my understanding is not great of this topic! $\endgroup$ – Adam apple Mar 21 '17 at 19:30

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