Simply Armonic Movement and k constant

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Plat00n
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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:

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

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

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

I'm ok since here?

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

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

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:
[tex]\frac {\partial \psi (x,t)}{\partial x^2} = \frac 1 v^2 \frac {\partial^2 \psi (x,t)}{\partial t^2}[/tex]
And this, if I'm not wrong, must to satisfy the independent of time Helmholtz equation:
[tex]\frac {d^2 A(x)}{dt} + k A(x) = 0[/tex]
I'm ok since here?
If it's ok, the solution of the first equation could be:
[tex]\psi (x,t) = A e^{kx-wt}[/tex]
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:
[tex]\frac {\partial \psi (x,t)}{\partial x^2} = \frac 1 v^2 \frac {\partial^2 \psi (x,t)}{\partial t^2}[/tex]
And this, if I'm not wrong, must to satisfy the independent of time Helmholtz equation:
[tex]\frac {d^2 A(x)}{dt} + k A(x) = 0[/tex]
I'm ok since here?

Not quite. It should be:

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

If it's ok, the solution of the first equation could be:
[tex]\psi (x,t) = A e^{kx-wt}[/tex]
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 [itex]k[/itex]'s are the same.