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Before the ball is even released, he seems to be emphasizing in his posts that the ball does not have any "stored" energy.
That's what my questions are pertaining to.
.99
When the ball is at its high point it does not have stored energy, in fact it has no energy at all, the energy comes from gravity when it starts to fall and when it hits the floor this is when it stores its energy so as to counter gravity to rise up again.
A battery stores energy which was put into it in the first place, and to put this energy in a change took place in the battery, the ball did not change when it was at its high point.
Just a brief take on the bouncing ball. The ball is a charged capacitor, its voltage in this case is the Mgh potential energy plus the 1/2Mv-squared kinetic energy. When the ball falls the gpe + kpe are a constant, i.e.; a constant voltage. Each time the ball bounces you loose a little puff of energy in the deforming ball, and hence the voltage across the ball drops. So the bouncing ball's voltage takes multiple discrete steps down in time, down to zero. The starting gpe gets converted into heat in the ball. You are basically discharging a capacitor.
You got much better scope traces this time, congratulations. I have a theory for you: In the first one with fast switch operation, I think that I can explain the ringdown. At the switch-off, can you see that little extra positive spike? Wow, that looks like what .99's PSpice model put out also. That's the coil shooting into high voltage territory and pumping a tiny amount of juice through the MOSFET just before the MOSFET fully switches off and the diode switches on. We know the MOSFET switches off very fast, so the ringing across the shunt resostor is happening after that event takes place. It's important to keep this in mind.
I think the ringdown you see there is along one specific wire length in your circuit build. Think of the full length of wire that goes from the MOSFET source pin through the shunt resistor to the battery ground. For the sake of argument assume that it is 12 inches long, and the shunt resistior is about half way down the wire. The length of wire has an inductance. One end of the wire is attached to the battery ground. The other end of the wire is floating now, and has a stray capacitance to ground. So the length of wire is an LC resonator with one end tied to ground potential. When the current is cut off the LC resonator is storing energy in the inductance of the wire. This rings the bell of the LC resonator and it resonates right through the shunt resistor. So the ringing you see is the wire resonator discharging, and this does not affect the battery.
> a charged inductor has current going through it, and no voltage across it's terminals'? I presume it's a misprint? In other words '... the inductor has current and voltage.'?
Some of the basics: When DC is going through an ideal inductor there is zero volts across it. To calculate the energy stored in it you only have to factor in the current, not the voltage.
If you take a big spring, and put it in a vice, and tighten the vice up and just stare at the compressed spring, you are looking at your own muscle power times the amount of time you spent cranking the vice now being stored in the spring as a measurable amount of energy. The spring is not moving, it's just sitting there, so there is zero volts/velocity across the ends of the spring. That's the same as a coil with DC current runing through it.
Yes of course the voltage and the current happen simultaneously, I just did not mention it. The big hurdle is to understand the relationship between the voltage and current for coils and caps, because they are time-dependent and frequency dependent.
Yes of course the voltage and the current happen simultaneously, I just did not mention it. The big hurdle is to understand the relationship between the voltage and current for coils and caps, because they are time-dependent and frequency dependent.
MileHigh
With respect. It is my opinion, for what it's worth that these effects become time dependant and frequency dependant when they are needed for compliance to second laws.
Current definition reaches new levels of absurdity when applied to switching circuits. Again, with respect and in my opinion. I'm anxious to understand why such exotic and extraordinary explanations are required and why there is a total avoidance of the simple fact of regenerated current flow in terms of Inductive Laws as a result of a switched cycle. I'm not the expert here.
EDIT I may add that polarisation of the potential difference and the resultant path of current flow in the collapsing fields on the resistor would then, magically, have a clean clear path back through the battery as is evident in our measured results.
Last edited by witsend; 07-25-2009, 05:33 PM.
Reason: another point
Some of the basics: When DC is going through an ideal inductor there is zero volts across it. MileHigh
What is an ideal inductor? Is this a real inductor or a fictitious inductor? I can never get my mind around that term? Would you please explain it. Experimentally I have never found an inductor in a ciruit system which has current flow but no voltage. Never, ever, ever. And I experimented for 4 years on the trot.
Just to add a little more of an explination on the rubber ball. The ball AT NO TIME HAS STORED ENERGY untill it has been compressed like a spring, the time when it was compressed was when it hit the ground, then it had stored energy, which was released to move it upwards again.
Originally posted by Michael John NunnerleyView Post
Just to add a little more of an explination on the rubber ball. The ball AT NO TIME HAS STORED ENERGY untill it has been compressed like a spring, the time when it was compressed was when it hit the ground, then it had stored energy, which was released to move it upwards again.
Mike
Mike,
Do you agree or disagree that the terms "stored energy" and "potential energy" essentially mean the same thing?
An ideal inductor is a coil of wire where there is zero ohms of resistance in the wire.
A "really ideal" inductor is an ideal inductor with zero stray capacitance associated with it.
Superconductors form ideal inductors because they have no resistance.
In theory, an ideal inductor with current going through it can generate an infinitely high spike of voltage for an infinitely short amount of time when you open-circuit it.
Milehigh
You are not serious, when you state Voltage and Current happens simultaneous. Do you?
Like Flash and Thunder maybe?
About Coils, you think, you can do the same with any regular Coil, what you you do with Tesla Coils?
Standard Coils have most bad behaviour for generating or creating a Magnetfield.
Plus they have the highest inductive Resistance, what you can do with a Coil.
Nothing more worse then a standard wound left right Coil.
That just sounds all so wrong what you state here. Sorry.
Theorizer are like High Voltage. A lot hot Air with no Power behind but they are the dead of applied Work and Ideas.
An ideal inductor is a coil of wire where there is zero ohms of resistance in the wire.
A "really ideal" inductor is an ideal inductor with zero stray capacitance associated with it.
Superconductors form ideal inductors because they have no resistance.
In theory, an ideal inductor with current going through it can generate an infinitely high spike of voltage for an infinitely short amount of time when you open-circuit it.
MileHigh
Thanks for the explanation. As long as we're on the same page here. It's not actually being applied to experimental apparatus which is where I am obliged to focus. We're trying to establish measured reality. Nature as she is. Not as she should be. MileHigh, please tell me why you are not prepared to accept the 'reticulated current flow' as per gotoluc's description. Why can the simple inductive laws not be applied to the collapsing fields in the inductor? is my question.
Luc, Don't know if I'm missing you or what. Please advise. Were you running the same experiment as per your earlier diagram but with two batteries? And were the batteries run per your experiment done without a load?
I'm not sure what the experiment was. But if you were running with a load then your results were extraordinary. Be glad to hear from you?
Hi Rosemary,
my 3 tests were using a 12 vdc battery at source and an identical 12vdv battery in series on the flyback side instead of the bulb or resistor. So sorry, no resistors were used.
Originally posted by Michael John NunnerleyView Post
Just to add a little more of an explination on the rubber ball. The ball AT NO TIME HAS STORED ENERGY untill it has been compressed like a spring, the time when it was compressed was when it hit the ground, then it had stored energy, which was released to move it upwards again.
Mike
Exactly. The bouncing ball has properties that enable the 'bounce' but the bounce was not related to the velocity or force from the drop. It was 'regenerated' as a result of it's own properties of compression. Not sure if you mean to argue this point? But that's how I see it. If you dropped a stone and the ball - and both the same mass, then the stone would stay put. The ball would bounce. And bounce. And bounce. In decreasing increments until it finds a rest state. Evidently far more energy from a single release than is evident in the stone. Which of the two exceeds unity? Or do neither?
Do you agree or disagree that the terms "stored energy" and "potential energy" essentially mean the same thing?
.99
Disagree, because stored energy is a fact, past tense, and potential energy has not taken place yet, future tense. Stored energy will deteriate over time, as in the compressed rubber ball, if it remains compressed over time it will loose energy. Potencial energy is the future result of that stored energy. They are related but not the same
my 3 tests were using a 12 vdc battery at source and an identical 12vdv battery in series on the flyback side instead of the bulb or resistor. So sorry, no resistors were used.
Luc
Hi Luc. At last. I've been hanging around all day. Ok. I get it. You're just trying to see how often the one can recharge the other? I suppose you could calculate energy here but you'd need to establish losses and that's difficult. You cannot get a closed system - if that's what you were trying for.
Can I ask you a favour. Can you do our test? Are you up for it? In other words just our simple circuit. Aaron will help you with the frequencies if needed. You and he can discuss the required parameters. It's just that I so trust your protocols.
I'm afraid guys - for the record - we do not have a perpetual motion thing going here. Just above unity at this stage. I think PM is possible but NOT in an electric circuit where the supply source relies on potential difference as currently (sorry for the apparent pun) applied.
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