Resistance and temp co-efficient?

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SUMMARY

The resistance of a conductor with a cross-section of 10 cm² and a specific resistance of 7.5 ohm cm at 0°C is calculated to be 90,000 ohm/km at 40°C. This calculation incorporates the temperature coefficient of the material, which is 0.005 per degree Celsius. The formula used is R = ρL/A, where ρ is the resistivity, L is the length, and A is the cross-sectional area. The increase in resistance is attributed to the temperature rise, resulting in a 9,000 ohm increase from its original resistance at 0°C.

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Homework Statement



A conductor has cross-section of 10 cm2 and specific resistance of 7.5 ohm cm at 0 degree C
what will be its resistance in ohm per/kilometer when the temperature is 40 degree C ?
take temperature co-efficient of the material is 0.005 / degree C

i can't find the solution of it. please give me solution if you can
please help me

Homework Equations


Resistance of a wire in Ω
R = ρL/A
ρ is resistivity of the material in Ω-cm
L is length in cm
A is cross-sectional area in cm²

The Attempt at a Solution

R = (7.5 Ω-cm)(L) / 10 cm²
R/L = 0.75 Ω/cmR/L = 0.75 Ω/cm x 100000 cm/km = 75000 Ω/km
R/L = 75000 Ω/km x [1+ (0.005/C)*40C]
R/L = 90000 Ω/km
 
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Therefore, the resistance of the conductor at 40°C would be 90,000 Ω/km. This calculation takes into account the temperature coefficient of the material, which indicates how much the resistance changes with temperature. In this case, the resistance increases by 0.5% per degree Celsius. So at 40°C, the resistance would be 9,000 Ω higher than at 0°C.
 

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