A copper wire has a resistance of 0.500 Ω at 20.0ºC , and an iron wire has a resistance of 0.525 Ω at the same temperature. At what temperature are their resistances equal?

-17.04

Explanation:

The resistance of an object varies with temperature and is given by the formula:

Where R = resistance at temperature T

= resistance at reference temperature

= Temperature coefficient of resistance

T = temperature in degree Celsius

= reference temperature.

For the copper wire:

R = 0.500(1 + 0.004041(20.0 - )

For the iron wire:

R = 0.525(1 + 0.005671(20.0 - )

When the resistance are equal for the two elements:

0.500(1 + 0.004041(20.0 - ) = 0.525(1 + 0.005671(20.0 - )

0.500(1 + 0.08082 - 0.004041) = 0.525(1 + 0.11342 - 0.005671)

0.000956775‬‬ = -0.0163‬

= -17.04

The temperature of equal resistance is -17.04

come closer and become far apart and become steam/gas