Extra Que for Interest: Voltage and Wire Resistance

AI Thread Summary
When a wire of a certain length, such as 40m, is connected to a voltage source like a 24V battery, the voltage does not remain constant throughout the wire due to resistance. As you measure voltage along the wire, such as at a 10m segment, the voltage will decrease because of the wire's resistance, leading to a voltage drop. The resistance can be calculated using the equation R = ρL/A, where ρ is resistivity, L is length, and A is cross-sectional area. Therefore, as you move away from the battery's positive terminal, the voltage decreases due to the wire's inherent resistance. Understanding this voltage drop is crucial for analyzing electrical circuits effectively.
jen333
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Hi! I was looking at notes about voltage and resistance, and this question popped into my head.

Homework Statement


If a certain length of wire ie)40m with an unknown resistance has a voltage of say 24V (random number) when hooked up to a battery, how does the voltage change throughout the circuit, or does it? ie) when a voltmeter is hooked up to a 10m segment of the wire anywhere on the wire, would the voltage increase or decrease?


Homework Equations


P=IV
R=pL/A


The Attempt at a Solution


I'm not sure, but if i were to guess I would think of the wire as any other resistor and assuming resistance is constant throughout predict the same voltage? I'm probably completely off, but it's worth a shot.

Thanks!
 
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By your second equation you have said you've traveled a 10m distance ... so what would the R be at that point?

Since it is something anyway, and if you are traveling from the positive terminal of the battery, then if there is a ΔR, there must be a ΔV.

Increase from the positive terminal? Does that really make sense? Of course the ΔV is going to be a drop.
 
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