Current Source in Parallel with Short Circuit

In summary: KVL is not violated because the voltage drop across the short circuit is zero and any other branches would have a voltage drop of zero as well since there is no current going through them. In summary, the conversation discusses a circuit with a 2 Amp current source in parallel with a short circuit and whether or not it is a self-contradictory combination of circuit elements. The answer key states that it is not contradictory because an ideal current source provides a given current regardless of the load, and the voltage across a short circuit is zero. The conversation also mentions the equations KVL, KCL, and Ohm's Law, and the student's initial confusion about the concept. After further explanation, they understand that KVL is not
  • #1
nickadams
182
0

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?
 
Physics news on Phys.org
  • #2
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?
 
  • Like
Likes nickadams
  • #3
What are the other choices you're given?
 
  • Like
Likes nickadams
  • #4
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
 
  • #5
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?
 
  • Like
Likes nickadams
  • #6
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
 

1. What is a current source in parallel with short circuit?

A current source in parallel with short circuit is a specific circuit configuration where a current source and a short circuit are connected in parallel. This means that the two components share the same nodes or connection points, allowing current to flow through both.

2. How does a current source in parallel with short circuit behave?

In this configuration, the current source will provide a constant current, while the short circuit will allow all the current to pass through it without any resistance. This results in the short circuit essentially "shorting out" the current source, causing the overall current in the circuit to be equal to the current source's value.

3. What are the applications of a current source in parallel with short circuit?

This circuit configuration is commonly used in electronic devices to provide a stable and regulated current to certain components. It is also used in testing and troubleshooting circuits, as the short circuit can be removed to isolate the current source and determine its function.

4. What are the advantages of using a current source in parallel with short circuit?

One advantage is that it provides a constant and stable current, which is useful in applications where precise current control is needed. Additionally, it allows for easy isolation and testing of the current source, making troubleshooting and maintenance more efficient.

5. Are there any limitations or drawbacks to using a current source in parallel with short circuit?

One limitation is that the short circuit will always consume all the current, making it difficult to control the overall current in the circuit. Additionally, the short circuit can also cause damage to the circuit if it is not properly sized to handle the current from the source.

Similar threads

Current through a circuit when the key is open
    • Introductory Physics Homework Help
2
Replies
42
Views
1K
Understanding Short Circuit Current Paths in Electrical Circuits
    • Introductory Physics Homework Help
Replies
4
Views
871
Understanding example in Wikipedia entry for open circuit voltage
    • Introductory Physics Homework Help
Replies
3
Views
552
Ohm's Law - Finding Source Voltage
    • Introductory Physics Homework Help
Replies
3
Views
526
Worst-case power consumed by a circuit with MOSFETs
    • Introductory Physics Homework Help
Replies
2
Views
296
When a short-circuit exists, how to find the current?
    • Introductory Physics Homework Help
Replies
4
Views
2K
Series RLC and Parallel RLC circuits
    • Introductory Physics Homework Help
Replies
15
Views
4K
Analyzing Bridge Circuit w/ Loop Currents
    • Introductory Physics Homework Help
Replies
6
Views
588
Current flowing in a branch in a circuit
    • Introductory Physics Homework Help
Replies
13
Views
1K
Finding the Current in a circuit
    • Introductory Physics Homework Help
Replies
6
Views
2K

Hot Threads

Recent Insights

Back
Top