Not sure what the initial temperature is

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The discussion revolves around calculating the temperature at which aluminum's resistivity is three times that of tungsten's resistivity at room temperature. The resistivity values provided for tungsten and aluminum, along with the temperature coefficient for aluminum, are crucial for the calculation. The initial assumption of 20 degrees Celsius as room temperature is questioned, as it may be lower than typical values used in such calculations. The user attempts to solve the equation but arrives at an incorrect temperature of 11.42 degrees Celsius. Clarifications on terms and units are requested to resolve the confusion in the calculations.
Gemy4
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Homework Statement



At what temperature will aluminum have a resistivity that is three times the resistivity of tungsten at room temperature?

Rt=5.6 X 10^-8 ohm*m (The resistivity coefficient of tungsten at 20 degrees celsius)
R0=1.59 x 10^-8 ohm*m (The resistivity coefficient of silver at 20 degrees celsius)
α =3.9 X 10^-3 degrees celsius ^- 1 (Temperature coefficient of resistivity for aluminum)

ΔT= Tf-Ti

I am not sure what the initial temperature is, I assume its 20 degrees celsius.

Homework Equations


Rt = R0 * ( 1 + α * ΔT)

The Attempt at a Solution



3Rt = R0 * ( 1 + α * ΔT)I get 11.42 degrees celsius which is wrong?
 
Last edited:
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Gemy4 said:

Homework Statement



At what temperature will aluminum have a resistivity that is three times the resistivity of tungsten at room temperature?

Rt=5.6 X 10^-8
R0=1.59 x 10^-8
α =3.9 X 10^-3
Room temperature = 20 C*

Homework Equations


Rt = R0 * ( 1 + α * ΔT)


The Attempt at a Solution



(3)Rt = R0 * ( 1 + α * ΔT)


I get 11.42 degrees celsius which is wrong?

Could you please define each of the terms that you're using, and include units on everything?
 


Sorry edited
 


Gemy4 said:
Sorry edited

That helps, but you define Rt as two different things (a bit confusing), and the units of resistivity are not Ohm/m.

Does the problem define "room temperature"? 20C is a little low for the room temperature number that I usually use...
 


Ok Thank you.
 
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