Current Source in Parallel with Short Circuit

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A 2 Amp current source in parallel with a short circuit is not considered a self-contradictory combination of circuit elements. The current source will direct all its current into the short circuit, resulting in zero voltage across it, which aligns with Ohm's Law. This situation does not violate Kirchhoff's Voltage Law (KVL) because the voltage drop is zero. The discussion clarifies that current can flow without a voltage difference when resistance is zero. Understanding this concept resolves the confusion regarding the apparent contradiction.
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Homework Statement



Which of the following are self-contradictory combinations of circuit elements?

- A 2 Amp current source in parallel with a short circuit.

Homework Equations



KVL- "the sum of voltages around a closed loop amounts to 0.
KCL- "the current into a node equals the current out of a node.
Ohm's Law- V= IR

The Attempt at a Solution



The answer key says this is not contradictory, but I don't see how we can have such a circuit... If we had a short circuit parallel to a current source wouldn't all the current go into that short circuit branch and ignore the other branches? Then we'd just have a loop of 2 Amp current with no voltage drop... Why wouldn't that violate KVL?
 
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An ideal current source provides a given current no matter what the load is. The voltage across it is equal to the generator current multiplied by the loading resistance, zero for a short-circuit. Where is contradiction?
 
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What are the other choices you're given?
 
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ehild said:
An ideal current source provides a given current no matter what the load is. The voltage across it is equal to the generator current multiplied by the loading resistance, zero for a short-circuit. Where is contradiction?

I just always thought that in order for current to flow between two points we need a voltage difference...

Bystander said:
What are the other choices you're given?

I understand the rest of them... It was only this one I was hung up on
 
nickadams said:
I just always thought that in order for current to flow between two points we need a voltage difference...

What is the voltage difference across zero resistance according to Ohm's Law?
 
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ehild said:
What is the voltage difference across zero resistance according to Ohm's Law?

V=IR so V=I*0=0. Ok I think I see now
 

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