Recent content by cristian1500

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    Obtain transfer function of a system and simulate it with a PID controller

    I want to tune my PID controller. For this I could either do this on-line using the controller on the system, or I could try to obtain the systems' transfer function and then simulate it off-line together with the PID controller to tune it to the desired behavior. I suspect the system is...
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    Undergrad Can Metals Ever Have an Electric Field Inside?

    it is known that in metals the electric field is zero because there are free charges inside that rearranges in such a way that it cancels the external electric field. If the external electric field is large enough, so large that all the free charge inside cannot rearrange itself to cancel the...
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    Graduate Can the wavefunction of a particle determine its position in space?

    I see. The wavefunction is complex! The real and imaginary parts have any physical significance? When do I use the current density in quantum mechanics?
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    Graduate Can the wavefunction of a particle determine its position in space?

    Hello I know that every particle has attached a wavefunction in quantum mechanics. How does a free particle move in quantum mechanics? The wavefunction has periodic zeroes, and the |wavefunction|^2 gives the probability of finding that particle...so does this mean that in space the...
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    Graduate Nuclear Scattering Applets - Potential & Plane Wave Expansion

    With an applet I can feel much better the physics. I found for example this simulation http://www.numathics.com/arens/scattering/ssObst.html The actual calculation is done with DWBA, but in order to understand how DWBA works I must have a physical intuition prepared.
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    Graduate Nuclear Scattering Applets - Potential & Plane Wave Expansion

    Hello I have trouble understandig nuclear reactions. Does anyone know some good scattering applets on a potential(of arbitrary shape;not 1D). I am interested also in discussing partial wave expansion. And if there exists an applet to show me how can I approximate a plane wave with...
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    What units are used when measuring Log(I) in Amperes?

    Not quite. The dB is out. I don't want to use the representation in dB. And as far as the dB is concerned I think it has no physical dimension: Log(Amps/Amps)=no phys units...now look at the problem below.I don't think that using the same units for I as for log(I) is correct. I want to...
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    What units are used when measuring Log(I) in Amperes?

    Hello I have a current through a simple circuit. What is the measuring unit of Log(I) where I is the intensity of the current measured in Ampers. Thanks