Why are voltages across wires close to zero?

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The discussion centers on why voltages across wires are close to zero, particularly in circuits with components like batteries, resistors, and light bulbs. It highlights that the low resistance of typical wires results in minimal voltage drop between two points along the wire, as described by Ohm's law. If the wire were significantly longer or had a smaller cross-section, a measurable voltage drop could occur. Participants emphasize the importance of measuring current and understanding resistance in these scenarios. Overall, the low voltage readings across wires are primarily due to their low resistance.
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Homework Statement


Why are voltages across wire close to zero? Or is it just a coincidence?



Homework Equations





The Attempt at a Solution

 
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Do you mean why is the voltage difference between 2 near points along an energized wire near 0?? Or do you mean why is the voltage difference between 2 wires each energized at near the same voltage and phase angle near 0? or something else? Please indicate your thoughts on this.
 
In class we used a voltmeter to measure the voltage across the different parts of a circuit. In the circuit there was a battery, resistor and light bulb. they just had us measure in parallel using the voltmeter all the parts including the wire. One of our questions afterwards was why are some of the voltages near zero?
 
Kourtney0115 said:
In class we used a voltmeter to measure the voltage across the different parts of a circuit. In the circuit there was a battery, resistor and light bulb. they just had us measure in parallel using the voltmeter all the parts including the wire. One of our questions afterwards was why are some of the voltages near zero?

May I assume that at some point in the exercise you were able to either measure the current going through the wires, or deduce the current going through the wires in some other way? You might want to invoke Ohms' law in your answer, noting that the resistance of a typical wire is quite small.
 
Kourtney0115 said:
In class we used a voltmeter to measure the voltage across the different parts of a circuit. In the circuit there was a battery, resistor and light bulb. they just had us measure in parallel using the voltmeter all the parts including the wire. One of our questions afterwards was why are some of the voltages near zero?
The resistance of the wire (ohms/meter) is rather low, so there is very little votage drop between 2 points on the wire. If the wire was very long, or very small, the resistance would be greater, and then there could be a measurable voltage drop between the 2 points.
 

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