Not sure what the initial temperature is

[Gemy4]

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 celcius)
R0=1.59 x 10^-8 ohm*m (The resistivity coefficient of silver at 20 degrees celcius)
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 celcius.

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?

 

[berkeman]

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?

 

[Gemy4]

Sorry edited

 

[berkeman]

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...

 

[Gemy4]

Ok Thank you.