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# Voltage and power through steel pipe

## Voltage and power through steel pipe

(OP)
Dear people,

In my education I've had basic electronics. But there is 1 thing I never understood. If i have a voltage source, let's say 5 volt, and I connect a steel or coper wire directly from the plus to the minus, what will happen? Because if u calculate the resistance of the wire its extremely low and when u apply the law of Ohm, the current will be extremely high. Is this what happens?
This also happens when using a small steel pipe. I've simulated this with a small steel pipe of length 0.2m and radius of 0.003m which has a resistance of 1270 micro-ohms. Also, why is the voltage displayed as 2.44444V?

Kind regards,
Willem

### RE: Voltage and power through steel pipe

The voltage is displayed in reference to the ground. Because the ground has connection with the circuit, it sort of becomes the mid point for the voltage.
The voltage will not equal 5V because of internal resistance of the battery.
Must be some kind of battery to be able to source close to 2MW of energy.

### RE: Voltage and power through steel pipe

Usually there is a flash, sometimes a bang. Normally it also ruins the battery terminal and takes a chunk out of the conductor.

Look up battery internal resistance: https://data.energizer.com/pdfs/batteryir.pdf for example.

### RE: Voltage and power through steel pipe

Did you have some reason for doubting Ohm's Law?

It looks like your simulation didn't actually have a ground reference, so the actual ground wound up roughly halfway between the negative and positive terminals of the battery; this is borne out by the fact that the negative end of the battery is shown as -2.5556 V, while the other terminal is shown as +2.4444, which, coincidentally add up to 5.0000 V, so no mysterious internal resistance is needed to explain the result. Note also, the current shown is nearly exactly 5 volt/1.270 milliohm = 3937.0079 amp, which, again, indicates that no internal resistance was modeled.

In any case, since you didn't model the internal resistance of the battery, you got an absurd current that a real battery can't produce. A real battery, ala AA, would have an internal resistance between 100 and 150 milliohm, resulting in between 10 and 15 A current into a dead short.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
FAQ731-376: Eng-Tips.com Forum Policies forum1529: Translation Assistance for Engineers Entire Forum list http://www.eng-tips.com/forumlist.cfm

### RE: Voltage and power through steel pipe

Maybe congress is trying to repeal Ohms law, again.

### RE: Voltage and power through steel pipe

by the way, "Voltage and power through steel pipe" is a terrible idea, in general, shorts, damage to circuitry, etc.; exposed live conductors (wires) is BAD, unless the circuit is specifically designed for something like that, like a digital volt meter

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
FAQ731-376: Eng-Tips.com Forum Policies forum1529: Translation Assistance for Engineers Entire Forum list http://www.eng-tips.com/forumlist.cfm

### RE: Voltage and power through steel pipe

(OP)
Thank you all for the answers, as you said @IRstuff I completely forgot about the internal resistance so I got absurd results from my simulations (I've made other simulations aswell but this was just an example for the problem). Thank you for correcting me.

### RE: Voltage and power through steel pipe

Dear Mr Willem19 (Civil/Environmental)(OP)21 Dec 22 10:23
"....I completely forgot about the internal resistance so I got absurd results from my simulations (I've made other simulations aswell but this was just an example for the problem)...."
I notice that so far all the learned advice are based on "electrical" such as Ohm's Law etc.... In view that you are from a different discipline/engineering (civil/environmental), we may not be looking/missed the core reason of your question.
It would be more fruitful if you are willing to disclose why are you carrying out this simulation? For what purpose/application ? With clear "objective" in mind, we may be able to assist.
Che Kuan Yau (Singapore)

### RE: Voltage and power through steel pipe

#### Quote:

by the way, "Voltage and power through steel pipe" is a terrible idea, in general, shorts, damage to circuitry, etc.; exposed live conductors (wires) is BAD, unless the circuit is specifically designed for something like that, like a digital volt meter
Underground pipe thawing with a welder?

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

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