How to Calculate the Resistance of Nichrome in a Series Circuit with Graphite?

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To calculate the resistance of nichrome in a series circuit with graphite, the total resistance is given as 5.8 ohms, which is independent of temperature. The temperature coefficients of resistance for graphite and nichrome are -0.0005 K⁻¹ and 0.0004 K⁻¹, respectively. The resistance of the graphite wire (R_G) and the nichrome wire (R_N) can be expressed in relation to each other using these coefficients. The key is to set up equations that incorporate these resistances and their temperature coefficients. This approach will lead to determining the resistance of the nichrome wire at the reference temperature.
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Homework Statement
Two wires are connected in series. One made of coal , other one of nichrome. Series resistance is 5.8 ohms , what is the resistance of nichrome wire? Temperature coef. of resistance of coal -0.0005K^-1 , 0.0004K^-1 of nichrome
Relevant Equations
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I don't really have any equations or idea how to solve this. I searched for relevant equations and only R=Rref(1+α(T-Tref)) pops up. I wasn't given any temperatures so I guess there must be some other way to solve this. Maybe anyone has idea how to approach this?
 
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Also it's mentioned that this compounds resistance isn't affected by temperature. so maybe that would make difference
 
Ugnius said:
Also it's mentioned that this compounds resistance isn't affected by temperature. so maybe that would make difference
Yes, that's critical. It let's you find the ratio of the two lengths. But there still doesn't seem to be quite enough info. Are you sure you have stated it completely?
(Coal?)

Edit: it let's you find the ratio of the resistances, not the ratio of the lengths, so it is enough information.
 
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So this is the statement in my native language, i will translate it word by word.
E27. In order to get a conductor , with resistance independant from temperature , we combine coal and nichrome wires in series. If that stated combination has a resistance of 5.8 ohm , what is resistance of nichrome? αcoal=-0.0005K-1 , αnichrome=0.0004K-1. Thats it.
 
Ugnius said:
View attachment 290949
So this is the statement in my native language, i will translate it word by word.
E27. In order to get a conductor , with resistance independant from temperature , we combine coal and nichrome wires in series. If that stated combination has a resistance of 5.8 ohm , what is resistance of nichrome? αcoal=-0.0005K-1 , αnichrome=0.0004K-1. Thats it.
Maybe the question is this:

A graphite wire and a nichrome wire are connected in series. Their total resistance is 5.8Ω and is independent of temperature.

For some reference temperature [probably 20ºC but it doesn’t matter] the temperature coefficients of resistance of graphite and nichrome are -0.0005K⁻¹ and 0.0004K⁻¹ respectively.

What is the resistance of the nichrome wire at the reference temperature?
_________

Hint: Call the resistances of the graphite and nichrome wires at the reference temperature ##R_G## and ##R_N##. Can you write down any equations, based on the information in the question, using ##R_G## and ##R_N##?
 
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