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Originally posted by ian619
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Power is energy/time.
"Instantaneous" doesn't come into it because instantaneous means "in no time", which would mean infinite power which would mean that we're all in a lot of trouble.
Interestingly, if you could sustain that infinite power over a finite time period, you would have an infinite amount of energy and therefore be able to accelerate something through the speed of light.
Who was asking about that?
An electron has NO power, it has energy.
Electrical current is the FLOW of electrons (or, more precisely, positively-charged holes flowing in a direction opposite to the flow of electrons) which carry energy. the electrons move relatively slowly but electricity moves at something approaching the speed of light because the charge from the elctrons moves across atoms more quickly than the electrons themsleves. i.e. an electron arriving on an atom forces one to leave from the other side of the atom sooner than the electron itself can get across to the other side of that atom - think Newton's Cradle.
This theory, incidentally, considers both the particle nature of electrons and their wave nature, but since all this has nothing to do with how much power a 2.4 lump chucks out I'm going back to contemplating how to determine whether my wheel-bearing's stuffed or whether I really do need to dismantle the diff.
Meantime, please don't go setting off any more universe-critical events without letting us know first. It's not the sort of surprise people expect at Santa-time (or whatever we're allowed to call it now).
Oh look dear! A new universe. Er, thanks.Comment
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Originally posted by NFC
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Twas me NFC, Think i read somewhere that if you exceeded the speed of light
one of two things would happen, you would either dissappear or you would see yourself comeing (done the latter)
Too young to die and too old to give a tossComment
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People see me coming all the time!Originally posted by ian619Twas me NFC, Think i read somewhere that if you exceeded the speed of light
one of two things would happen, you would either dissappear or you would see yourself comeing (done the latter)
Cutting steps in the roof of the worldComment
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Power (in DC case) is Voltage / Current. Time does not come into this.Originally posted by NFCCutting steps in the roof of the worldComment
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Sigh here we are then...........
If a thin wire is connected in a circuit end to end with a thick wire, it turns out that the charges in the thin wire move faster. This makes sense, it works just like water in rivers. If a huge wide river moves into a narrow channel, the water speeds up. When the channel opens out again downstream, the river slows down again. The flow in a very thin wire will be tend to be fast, even if the value of current is fairly low. This means that we can't know the speed of the flowing charge-sea unless we know how thick the wires are.
If a copper wire is connected into a series circuit with an aluminum wire of the same diameter, the charges in the copper will flow slower. This occurs because there is one movable charge per each atom in the metals, but there are more atoms packed into the copper than into the aluminum, so there is more charge in each bit of copper. When the charge-sea flows into the copper, it gets packed together and slows down. When it flows out into the aluminum, it spreads out a bit and speeds up. This means that we cannot know how fast the charges flow unless we know how dense the charge-sea is within the metal.
The speed of electric current.......
Since nothing visibly moves when the charge-sea flows, we cannot measure the speed of its flow by eye. Instead we do it by making some assumptions and doing a calculation. Let's say we have an electric current in normal lamp cord connected to bright light bulb. The electric current works out to be a flow of approximatly 3 inches per hour. Very slow!
Bulb power: about 100 watts, about 100V at 1A
Value for electric current: I = 1 ampere
Wire diameter: D = 2/10 cm, radius R=.1cm
Mobile electrons per cc (for copper, if 1 per atom): Q = 8.5*10^+22
Charge per electron: e = 1.6*10^-19
The equation:
cm/sec = ________I_______ = .0023 cm/sec = 8.4 cm/hour
Q * e * R^2 * piComment
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Thats not from the oil change bible...
Must keep the wires to the garage short, I hate waiting for the electric to get there when I switch the lights on.
Cutting steps in the roof of the worldComment
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P=IV Power = Amps x Volts and the answer comes in what unitsOriginally posted by Apache
WATTS. What is a watt ? 1 watt is 1 joule/second
POWER is a measure of what a unit of energy can achieve in a period of time.
TIME DOES COME IN TO IT.
anorak back in the cupboard again and I definitely give up now.
BogusСви можемоComment
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No, I'm gonna continue to argue an impossible angle...Originally posted by Bogus
Erm...
errr...
LOOK OVER THERE!!!!!!!
<gone>
Cutting steps in the roof of the worldComment
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Oops, I pressed the wrong button, meant to hit * rather than /.Originally posted by Bogus
Anyway, we're all entitled to our views. If I want instantaneous power, I'll have it! Now where did I put my perpetual motion machine...Cutting steps in the roof of the worldComment
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Originally posted by Apache
It's parked outside with a 5" lift and four spotlights on it, innit?Comment
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Perpetual motion machines dont use nearly as much diesel as that thing!Originally posted by BUSHWHACKERCutting steps in the roof of the worldComment
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Originally posted by Apache
How does yours work, does it work by using the first laws of thermodynamics or the second?Comment
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Have you only got ywo laws?
Pah! In my universe we have lots more! Mine works on the 55th revision of the 8th laws, version 3.88
(I had to update them to take electicity speed into account)Cutting steps in the roof of the worldComment
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