# Not sure what the initial temperature is

• Gemy4
In summary, the question asks for the temperature at which aluminum will have a resistivity three times that of tungsten at room temperature. Using the equation Rt = R0 * (1 + α * ΔT) and given values of Rt, R0, and α, it is possible to solve for the change in temperature (ΔT) using the assumption that the initial temperature is 20 degrees Celsius. However, it is unclear what the exact definition of "room temperature" is in this problem.

## 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?

Last edited:

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.