Does Wire Length Affect Resistivity in Electrical Conductors?

Thread starter ImStress
Start date May 12, 2019
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Length Resistivity Wire

In summary, resistivity is a measure of a material's ability to resist the flow of electric current and is affected by factors such as temperature and impurities. Wire length plays a role in determining the resistance of a wire, as the longer the wire, the higher its resistance. The formula for calculating resistance is R = ρ x L/A. Temperature can also affect resistivity, as it generally increases with higher temperatures. To reduce resistance in a wire, one can use a material with a lower resistivity, decrease the length of the wire, use a thicker wire with a larger cross-sectional area, and keep the wire at a lower temperature.

May 12, 2019

ImStress

Homework Statement: A length of aluminium wire having a cross-sectional area of 6 cm2 has a resistance of 6 Ω at a given temperature. Given the resistivity of aluminium is 5 x10-8 Ω-m, calculate the length of the wire in meters. (keep two decimal places)

Relevant Equations: R=Pl/A

L=Ra/P
=6x0.0006/5x10^-8
=72000

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May 12, 2019

scottdave

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Your calculation looks correct. The answer should have units on it. What is your question?
If you think it is too big, think about the size of a 6 square centimeter circle (cross section)

1. What is resistivity?

Resistivity is a measure of a material's ability to resist the flow of electric current. It is denoted by the symbol ρ and is measured in ohm-meters (Ωm).

2. How does wire length affect resistivity?

The longer the wire, the higher its resistance and therefore, higher resistivity. This is because a longer wire offers more resistance to the flow of electrons compared to a shorter wire.

3. What is the relationship between resistivity and wire length?

The relationship between resistivity and wire length is directly proportional. This means that as the wire length increases, the resistivity also increases.

4. How can resistivity and wire length be calculated?

Resistivity can be calculated using the formula ρ = RA/L, where R is the resistance of the wire, A is the cross-sectional area of the wire, and L is the length of the wire. Wire length can be measured using a ruler or measuring tape.

5. What are some factors that can affect the resistivity of a wire?

Some factors that can affect the resistivity of a wire include the type of material used, temperature, and impurities in the material. For example, materials with high conductivity, such as copper, will have lower resistivity compared to materials with low conductivity, such as rubber.