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Electroboom: How Right IS Veritasium?! Don't Electrons Push Each Other??
electrodacus:
--- Quote from: dunkemhigh on July 04, 2022, 09:31:51 am ---
And, actually, you didn't answer the question. You go on about how one circuit is 1V/1W and the other is 2V/2W and that's exactly the point! Despite that difference, there is still 1A going along that top wire.
--- End quote ---
You can not look at current only as that is just one part of power and thus energy.
The number of electrons that will travel through a section of wire every second at 1A is 6241509128999772160
But it is also important to know the electrical potential as that is what accelerates those electrons.
So 1V * 1As = 1Ws = 1 Joule
while 2V * 1As = 2Ws = 2 Joule
Again to give an analogy. Say you have a small pinhole (equivalent to resistance) in your tire so you're losing energy at some rate.
Say 1000 molecules of air are lost every second (equivalent with number of electrons) at 200kPa (equivalent with electrical potential)
You can now have a tire with a smaller pinhole that also loses 1000 molecules per second but pressure is 300kPa and that means you lose more energy than in the first case even if you lose the same number of air molecules because those 1000 molecules are accelerated by a pressure 2x larger.
When you go to charge the tire with say an electric compressor you will see that more energy will be used to push 1000 molecules when you have 300kPa in the tire vs when you have just 200kPa with say ambient pressure of 100kPa.
SiliconWizard:
Electroboom just inserted another coin! :popcorn:
PlainName:
--- Quote ---So 1V * 1As = 1Ws = 1 Joule
while 2V * 1As = 2Ws = 2 Joule
--- End quote ---
There is the same voltage across the wire in each case: in the first it is 1Vbat - 1Vres, and in the second it is (1Vbat+1V) - (1Vres+1Vres). This is, after all, what the last few pages have been about. We KNOW there is 1W and 2W, but how does this wire know that?
--- Quote --- Say you have a small pinhole (equivalent to resistance) in your tire
--- End quote ---
The wire is not limiting the current or potential, so is not equivalent to a pinhole. The potential difference is the same, so it's not equivalent to your air pressure.
electrodacus:
--- Quote from: dunkemhigh on July 04, 2022, 08:21:45 pm ---There is the same voltage across the wire in each case: in the first it is 1Vbat - 1Vres, and in the second it is (1Vbat+1V) - (1Vres+1Vres). This is, after all, what the last few pages have been about. We KNOW there is 1W and 2W, but how does this wire know that?
--- End quote ---
For anyone that draws a wire in a schematic it just means an ideal conductor with no resistance no inductance and no capacitance (this does not exist in real world).
--- Quote from: dunkemhigh on July 04, 2022, 08:21:45 pm ---The wire is not limiting the current or potential, so is not equivalent to a pinhole. The potential difference is the same, so it's not equivalent to your air pressure.
--- End quote ---
The wire (real wire made out of a room temperature metal) is a resistor so yes it limits the current the same as a pinhole limits the air flow.
In your example you can take a 58cm copper wire with a section of 0.01mm2 that will have a resistance of about 1Ohm and connect the wire across the terminals of a 1V battery.
Or you can take a wire twice as long 1.16m same 0.01mm2 cross section and connect it across a 2V battery or if you prefer across two 1V batteries connected in series which means actually the same thing. You do not call a 9V battery a 6x 1.5V batteries in series.
So yes that 1.16m long wire limits the current that flows through it to 1A if the supply is 2V.
PlainName:
--- Quote ---In your example you can take a 58cm copper wire with a section of 0.01mm2 that will have a resistance of about 1Ohm and connect the wire across the terminals of a 1V battery.
--- End quote ---
Only if we wanted to to plonk a dead cat on the table. Just take it that this is a normal wire with a resistance that is negligible compared to everything else. Like normal wires.
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