# Difference between a short circuit and a parallel circuit?

What's the difference between a short circuit and a parallel circuit?
In a short circuit, my teacher told me that no current will passs through the more resistive path. I doubt it. If this is wrong, then I could distinguish the difference and similarities between them.
If not, I really need someone's help.

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Pengwuino
Gold Member
A short circuit is where a piece of metal touched metal in the circuit and resulted in a path where teh current flows directly to the opposite end of the battery while bypassing all or a huge part of the circuit (or any part it was suppose to go through for that matter). These are basically flaws in a majority of cases or an accident. If you have a circuit and you grab a piece of wire (insulated of course) and touched the battery's negative and positive terminals, this would create a short circuit. The current is going to flow through the wire your holding instead of the circuit you have set up. This is what people call a short circuit.

A parallel circuit is where current flows in 2 or more different paths at a certain point in the circuit.

This is opposed to a SERIES circuit which i think is what you are thinking of. A series circuit is where the current only has 1 path to flow.

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Short Circuit

It is the process of joining two terminals of a battery/cell with a simple wire of very little resistance/no resistance , which will often to lead to sparking.When you join two terminals (+ve and -ve) with a simple wire , you are basically equating two different potentials with one single wire lead which will lead to sparking.

Parallel Circuit

There are basicallt two types of arrangement of components(resistances/inductors/capacitors), in case of resistors in parallel , it simply means that the resistors will have same potential difference along them.In series the current along the resistors in series will be the same and in parallel, the potential difference along the resistors in parallel will be the same.

BJ

Doc Al
Mentor
primarygun said:
What's the difference between a short circuit and a parallel circuit?
In a short circuit, my teacher told me that no current will passs through the more resistive path. I doubt it. If this is wrong, then I could distinguish the difference and similarities between them.
I think I know what you're thinking: That the short path and the resistive path are just two parallel branches with independent currents. As long as the voltage across each branch remains the same, the current across the resistive branch will still flow. The problem is assuming that the voltage source will be unaffected by the extremely high current demand place on it due to the short. In a real voltage supply, most of the voltage would be dropped across the internal resistance of the source, leaving very little to produce any current through the resistive path.

Doc Al said:
I think I know what you're thinking: That the short path and the resistive path are just two parallel branches with independent currents. As long as the voltage across each branch remains the same, the current across the resistive branch will still flow. The problem is assuming that the voltage source will be unaffected by the extremely high current demand place on it due to the short. In a real voltage supply, most of the voltage would be dropped across the internal resistance of the source, leaving very little to produce any current through the resistive path.
That's what I think but I am not sure whether it is correct.
The difference between a parallel circuit and a short circuit is the difference in the resistance of the two "path", isn't it?
If the resistances are the same---> parallel circuit
If they are not the same---> short circuit.
Am I correct?

+ve ----- -ve
|111111111|
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|------|

What happens to the current if the wire added later to the circuit is more resistive?How about if they have same resistance?

Pengwuino
Gold Member
No that is not correct.

Parallel circuits can have different or even the same resistances. A short circuit is actually a parallel circuit but the "short" has VASTLY less resistance then the rest of the circuit so almost all of the current travels through the "short".

In that diagram, if the new wire is more resistive, less current will flow through the first wire but the new wire will have a lot less current then the first wire. Both currents will add up to the original. If they have teh same resistance, they will both recieve the same current.

Pengwuino said:
No that is not correct.
Parallel circuits can have different or even the same resistances. A short circuit is actually a parallel circuit but the "short" has VASTLY less resistance then the rest of the circuit so almost all of the current travels through the "short".
.
almost, right?
Will a light bulb on the old wire glows if the new wire has a lower resistance?

In that diagram, if the new wire is more resistive, less current will flow through the first wire but the new wire will have a lot less current then the first wire. Both currents will add up to the original. If they have teh same resistance, they will both recieve the same current
If the original current is 10.
Get some figures for me for the new changes please
Such as old:4 , new:6

Pengwuino
Gold Member
Are we saying that the wire without the light bulb is just a lone wire?

If its just a wire and the old wire has a light bulb attached to it, the light bulb will not be on in any noticable way. The resistance of a lightbulb has far more resistance then a wire so most the current will go through the wire.

You cant really put # to it if all you say is "this is more resistive" or things like that. If you put a lightbulb in and a wire in.. the lightbulb will get like... 0.01 amps and the wire will get almost 10 amps if the battery can supply 10 amps and the wire and lightbulb's resistances create the need for 10 amps

If a statement says: Current will pass along the new wire instead of the old one as the new one is les resistive. Is it correct?

Pengwuino
Gold Member
MOST of the current will pass through the new wire.

thanksthanks