Calculating Resistance of 0.35m Copper Wire (20 AWG)

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Discussion Overview

The discussion centers on calculating the resistance of a 0.35-meter (1.148 feet) long copper wire with a diameter of 0.8118 mm (20 AWG). Participants explore methods for determining resistance, the implications for current flow, and requirements for connecting electrical devices such as switches.

Discussion Character

  • Technical explanation
  • Mathematical reasoning
  • Homework-related

Main Points Raised

  • One participant seeks to calculate the resistance of the wire and mentions a resistance value of 98.496 ohms per foot for copper wire, along with a current of approximately 0.031 amps when connected to two 1.5V AA batteries.
  • Another participant suggests using a voltmeter to measure the current before and after it flows through the wire, proposing to calculate current loss using Ohm's Law (I=V/R).
  • A third participant recommends the Hyperphysics website as a resource for understanding resistance calculations.
  • A later reply reiterates the initial inquiry and provides a calculation based on the American Wire Gauge (AWG) standard, stating that 20 gauge solid copper wire has a resistance of 10.15 ohms per 1,000 feet, leading to a calculated resistance of approximately 0.0116522 ohms for the specified length.

Areas of Agreement / Disagreement

Participants present various methods and calculations for determining resistance, but there is no consensus on a single approach or final answer. Different values and methods are discussed without resolution.

Contextual Notes

Some calculations depend on specific temperature conditions (20°C) and the accuracy of the resistance values cited. There may be assumptions regarding the uniformity of wire properties and the effects of temperature on resistance that are not explicitly stated.

.:Endeavour:.
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I want to know, how do you calculate the resistance of a copper wire with a length of 0.35 meters (1.148 feet) long with a diameter of 0.8118 mm (20 AWG). I found that the resistance of a copper wire in one foot is 98.496 \omega[\tex] and will be two 1.5V AA battery, so the current running through the wire is going to be approximately 0.031 amps. If If want to connect a switch to the wire, what should be the requirements for the switch or any other electrical devices?<br /> <br /> Here is where I got the resistance for the wire with a 20 AWG gage.<br /> <a href="http://www.eskimo.com/~billb/tesla/wire1.txt" target="_blank" class="link link--external" rel="nofollow ugc noopener">http://www.eskimo.com/~billb/tesla/wire1.txt</a>
 
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You could use a volt meter and measure the current coming from the source and the then the current after it has flowed through the wire and calculate the amount of current lost using ohms law I=V/R
 
.:Endeavour:. said:
I want to know, how do you calculate the resistance of a copper wire with a length of 0.35 meters (1.148 feet) long with a diameter of 0.8118 mm (20 AWG). I found that the resistance of a copper wire in one foot is 98.496 \omega[\tex] and will be two 1.5V AA battery, so the current running through the wire is going to be approximately 0.031 amps. If If want to connect a switch to the wire, what should be the requirements for the switch or any other electrical devices?<br /> <br /> Here is where I got the resistance for the wire with a 20 AWG gage.<br /> <a href="http://www.eskimo.com/~billb/tesla/wire1.txt" target="_blank" class="link link--external" rel="nofollow ugc noopener">http://www.eskimo.com/~billb/tesla/wire1.txt</a>
<br /> <br /> Per the AWG (American Wire Gauge) listed on the HyperPhysics website, 20 gauge solid copper wire @20 C (68 F) has a resistance of 10.15 ohms per 1,000 feet, which equates to .01015 ohms per foot (.01015 ohms/ft * 1,000 feet = 10.15 ohms).<br /> <br /> Per your length of 1.148 feet, that would equate to .0116522 ohms (.01015 ohms/ft * 1.148 feet = .0116522 ohms).
 

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