Resistance in a Wire (coursework Evaluation)

[Jozers]

To get the full marks for my gcse coursework "how does length affect the resistance in a wire?" I need to provide an alternative experiment that I could perform if I were to redo the investigation. I have already calculated resistance in circuit using ohm's law and predicted results using the R=ρL/A. Does anyone have any suggestion to what I could do? I haven't had any luck researching this, although my teacher hinted that I could do something with variable resistor to control the resistance but I have no idea how. Please remember this must relate to the length not wire temperature or cross-sectional area.

Thanks
Jozers

 

[OlderDan]

To get the full marks for my gcse coursework "how does length affect the resistance in a wire?" I need to provide an alternative experiment that I could perform if I were to redo the investigation. I have already calculated resistance in circuit using ohm's law and predicted results using the R=ρL/A. Does anyone have any suggestion to what I could do? I haven't had any luck researching this, although my teacher hinted that I could do something with variable resistor to control the resistance but I have no idea how. Please remember this must relate to the length not wire temperature or cross-sectional area.

Thanks
Jozers

Have you ever used one of those big slide wire rheostats as a variable resistor?

http://www.thesciencefair.com/Merchant2/merchant.mvc?Screen=PROD&Product_Code=1856-2&Category_Code=ET

Knowing how it works might give you some ideas. You might also want to find out about the Wheatstone bridge if you have not already encountered it.

 

[kyle8921]

I would suggest that you could perform an experiment using different materials for the wire. This would allow you to investigate how the material of the wire affects its resistance and how it compares to the results obtained from changing the length of the wire.

To do this, you could use wires made of different materials such as copper, aluminum, and nichrome. You can then measure the resistance of each wire at different lengths and compare the results. This will provide a more comprehensive understanding of how the material of the wire affects its resistance, in addition to the length.

Another alternative experiment could be to investigate the effect of temperature on resistance in a wire. To do this, you could use a variable resistor to control the temperature of the wire and measure the resistance at different temperature levels. This will allow you to see how temperature affects the resistance of the wire and how it compares to the results obtained from changing the length.

Furthermore, you could also explore the effect of wire thickness on resistance by using wires of different diameters. This will allow you to investigate how the cross-sectional area of the wire affects its resistance and how it compares to the results obtained from changing the length.

In conclusion, there are many alternative experiments that you could perform to investigate the relationship between length and resistance in a wire. The key is to vary one factor at a time while keeping others constant, and to compare the results to gain a deeper understanding of the factors that affect resistance in a wire.