Simply Armonic Movement and k constant

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The discussion centers on the variable "k" in the context of harmonic simple movement and its relation to wave equations. The original poster questions whether "k" in the wave equation is the same as "k" in the Helmholtz equation. A correction is provided, indicating that the Helmholtz equation should include "k^2" rather than "k." After this adjustment, it is confirmed that both instances of "k" refer to the same value. The conversation clarifies the relationship between the equations and the correct formulation needed for consistency.
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I have a question on "k" of an armonic simple movement.

If we take the equation of a wave, this is:

\frac {\partial \psi (x,t)}{\partial x^2} = \frac 1 v^2 \frac {\partial^2 \psi (x,t)}{\partial t^2}

And this, if I'm not wrong, must to satisfy the independent of time Helmholtz equation:

\frac {d^2 A(x)}{dt} + k A(x) = 0

I'm ok since here?

If it's ok, the solution of the first equation could be:

\psi (x,t) = A e^{kx-wt}

Is this "k" the same that the "k" in Helmholzt equation? Is there any mistake in this?

Plat00n.
 
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Plat00n said:
I have a question on "k" of an armonic simple movement.
If we take the equation of a wave, this is:
\frac {\partial \psi (x,t)}{\partial x^2} = \frac 1 v^2 \frac {\partial^2 \psi (x,t)}{\partial t^2}
And this, if I'm not wrong, must to satisfy the independent of time Helmholtz equation:
\frac {d^2 A(x)}{dt} + k A(x) = 0
I'm ok since here?
If it's ok, the solution of the first equation could be:
\psi (x,t) = A e^{kx-wt}
Is this "k" the same that the "k" in Helmholzt equation? Is there any mistake in this?
Plat00n.


Nobody can help me a little?
 
Plat00n said:
I have a question on "k" of an armonic simple movement.
If we take the equation of a wave, this is:
\frac {\partial \psi (x,t)}{\partial x^2} = \frac 1 v^2 \frac {\partial^2 \psi (x,t)}{\partial t^2}
And this, if I'm not wrong, must to satisfy the independent of time Helmholtz equation:
\frac {d^2 A(x)}{dt} + k A(x) = 0
I'm ok since here?

Not quite. It should be:

\frac {d^2 A(x)}{dx^2} + k^2 A(x) = 0

If it's ok, the solution of the first equation could be:
\psi (x,t) = A e^{kx-wt}
Is this "k" the same that the "k" in Helmholzt equation? Is there any mistake in this?

If you use the corrected version of the equation that I posted, then yes the k's are the same.
 
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