That's a lot of current. Make sure you calculate the power you'll be dissipating in each resistor before you turn anything on (they have a maximum power rating).
What Fluke model would that be and what range are you using it on when measuring the 20 microamps?
No, there are significant nonlinear effects that depend on temperature and (high) voltage, but none you should be worried about here. You're probably just seeing the effects of measuring a very low level of current with a piece of equipment that's not designed for measuring that range...
The equipment you're using to measure this isn't perfect. Typically, the lower the value of something you're measuring, the more inaccurate your equipment gets. That's only 20 microamps!
Try redoing your experiment with lower values of resistors. Aim for an effective resistance of a couple...
Here's a plot of your data with a polynomial degree 1 fit:
Doesn't look that bad. Fit gives an effective resistance of 30.85 kohm.
I'd take a guess that your measurements are a bit inaccurate down at those microamp levels. Have a look at the datasheet for your equipment for its accuracy at...
I assume you mean this function:
L(s) = 4/(s(.4s+1)(s+2))
Some thoughts to help you get to the answer:
Say you have two complex numbers z1 and z2, what is arg(z1 z2) and arg(z1/z2) in terms of arg(z1) and arg(z2)?
What happens to the angle of each factor in the denominator as s = jω, ω → 0?
Why is my black box not part of your reality? :cry:
The force can be either electric or magnetic, depending on your choice of reference frame. I assume you're analyzing this from the rest frame of the conductor, but that frame is no more fundamental than any other...
Sure, but that would also be the case for a nonideal current source.
What if I, in my EE studies, had a very difficult teacher. He/she had a preference for current sources and would almost never show a voltage source - practically everything would be modeled as current sources. I'd later come...
I'm not interested either in a discussion on the specifics of batteries, but it's one of the simplest examples I could think of of something you associate with a voltage source.
I'm not even talking about circuit theory, I just want to pose you the basic question: what is it about the behavior...
Okay, let's use this as a starting point. In the following, in the questions I might pose, I'm not trying to trick you or anything, I genuinely just want to present you an alternative viewpoint. Your line of reasoning is shared by many.
Let's assume non-ideal components, no hocus pocus. How do...
You'd agree that Maxwell's equations describe your physical point of view? If so, then voltage does not come before current or vice versa - there's no causal relationship between them.
@LvW, can you give an example of something you'd consider a voltage source? A battery perhaps, do you consider...
See my post #22. Depending on what you mean by 'dynamic stability' and what the feedback configuration is, that statement could mean any number of things. It certainly isn't true that negative feedback always reduces stability margins.
You could easily correct this by showing the math that...
You make vague statements that could mean any number of things, most of which are outright wrong. I don't consider that any sort of contribution.
If you really had a contribution to make, I would think you would be thrilled to show the math supporting it, since it would remove any doubt as to...
No, it's really not. There's all kinds of mathematical definitions for 'stability' and you haven't given one.
Reading this statement, you must be assigning some metric to 'dynamic stability', a measure of it, and you state that this metric gets degraded by applying negative feedback.
If you...
I can see from this what you'd like to show, but I don't think that'll address what you seem to be stating here in general.
Let me ask you this:
If I can show you a system which, in open loop, has a highly oscillatory response to a step input, do you mean to tell me that it's impossible to...