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short circuit

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paul_ma7

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If you connect the two terminal of a battery with a very low resistance that makes a short circuit, what is ..?
the lowest resistance that would not make a short circuit?
 
If you connect the two terminal of a battery with a very low resistance that makes a short circuit, what is ..?
the lowest resistance that would not make a short circuit?
I was thinking shades of grey regarding this. So I looked it up (so could you). Turns out the definition makes a lot of sense.

wikipedia said:
A short circuit (sometimes abbreviated to short or s/c) allows a current along a different path from the one intended. The electrical opposite of a short circuit is an "open circuit", which is an infinite resistance between two nodes. It is common to misuse "short circuit" to describe any electrical malfunction, regardless of the actual problem.

So if you intended to place the wire between the battery terminals it is not a short circuit because it is YOUR intended circuit. :)
 
Technically a short circuit just means a connection across any two points where the resistance is low enough to "too much" current to flow. "Too much" depends on the circuit itself. For a computer circuit 10mA may be too much. For a small motor, 50A might be too much. For a power grid it might be hundreds of amps. It's more of a qualitative term than a quantitative term.

For example, if you got a large 12V Lithium Polymer battery and connected a 12 ohm resistance across it so there was 1A of current flow and the battery could provide that current without overheating and the resistor is large enough to dissipate the heat, it's not a short circuit.

But if the battery was too small to provide that current without overheating or the resistor was too small so that it got too hot, it might be considered a short-circuit.

THe closest definition I can come up with for a short-circuit resistance is a resistance that is "for all intents and purposes" is zero, negligible, or very small for the circuit in question.
 
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A short circuit is simply a low resistance path close to 0 ohms. If you have a 3 ohm resistor hooked up to a battery and the load causes the battery to become overloaded, what you have is an overloaded battery, not a short based on the definition of what a short is.
For instance, if my 5V regulator is overloaded causing the output voltage to drop to 0.5V, I don't have a short but an overloaded condition. If I then measure 10 ohms of resistance on the 5V bus, it's not shorted, just overloaded. Remember a short will be close to 0 ohms such as your wire.
 
From my understanding, a short is an extremely low resistance across a power sourse - not intended.

It makes electronics PUFF and SMELL :D
 
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what about: a short circuit is if the resistance form pole to pole of the power source is lower than the source its internal resistance.

Robert-Jan
 
what about: a short circuit is if the resistance form pole to pole of the power source is lower than the source its internal resistance.

Robert-Jan
That sounds arbitrary. I like the Wikipedia definition that 3v0 posted.
 
If you connect the two terminal of a battery with a very low resistance that makes a short circuit, what is ..?
the lowest resistance that would not make a short circuit?

It is the lowest resistance possible, in a circuit were the battery, resistor or the fuse don't blow! (don't take this literally, the battery might not "blow")
 
It is the lowest resistance possible, in a circuit were the battery, resistor or the fuse don't blow! (don't take this literally, the battery might not "blow")
I have seen shorts on PC boards that were not "the lowest resistance possible".
 
if you are considering a path for a battery(not components) a short can also be regarded as the resistance(ideally 0) which drains the battery in the least amount of time. although conventional definitions have been given above.
 
As far as I'm concerned, there is only one definition of the term short circuit. It simply means an undesired electrical connection that compromises safety and/or causes the device/system to malfuction.
 
As far as I'm concerned, there is only one definition of the term short circuit. It simply means an undesired electrical connection that compromises safety and/or causes the device/system to malfuction.

I can live with that one :)

Robert-Jan
 
I'm with Hero999.

If it's not a short, is it a long?
 
Sometimes, I wish this forum would allow posts without the mandatory text...
 

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