"Hein ten Horn" <tenhornRemovE@ThiSraketnet.nl> wrote in message
news:469a27e2$0$333$e4fe514c@news.xs4all.nl...
> Ron Baker, Pluralitas! wrote:
>> Hein ten Horn wrote:
>>> Ron Baker, Pluralitas! wrote:
>>>> Hein ten Horn wrote:
>
>>>>> As a matter of fact the resulting force (the resultant) is
>>>>> fully determining the change of the velocity (vector) of
>>>>> the element.
>>>>> The resulting force on our element is changing at the
>>>>> frequency of 222 Hz, so the matter is vibrating at the
>>>>> one and only 222 Hz.
>>>>
>>>> Your idea of frequency is informal and leaves out
>>>> essential aspects of how physical systems work.
>>>
>>> Nonsense. Mechanical oscillations are fully determined by
>>> forces acting on the vibrating mass. Both mass and resulting force
>>> determine the frequency. It's just a matter of applying the laws of
>>> physics.
>>
>> You don't know the laws of physics or how to apply them.
>
> I'm not understood. So, back to basics.
> Take a simple harmonic oscillation of a mass m, then
> x(t) = A*sin(2*pi*f*t)
> v(t) = d(x(t))/dt = 2*pi*f*A*cos(2*pi*f*t)
> a(t) = d(v(t))/dt = -(2*pi*f)^2*A*sin(2*pi*f*t)
> hence
> a(t) = -(2*pi*f)^2*x(t)

Only for a single sinusoid.

> and, applying Newton's second law,
> Fres(t) = -m*(2*pi*f)^2*x(t)
> or
> f = ( -Fres(t) / m / x(t) )^0.5 / (2pi).

Only for a single sinusoid.
What if x(t) = sin(2pi f1 t) + sin(2pi f2 t)

>
> So my statements above, in which we have
> a relatively slow varying amplitude (4 Hz),
> are fundamentally spoken valid.
> Calling someone an idiot is a weak scientific argument.

Yes.
And so is "Nonsense." And so is your idea of
"the frequency".

> Hard words break no bones, yet deflate creditability.
>
> gr, Hein
>
>