Understanding Thermodynamics: Solving for Resistance and Temperature

[ice87]

another thermodynamics problem

For this one its a combination of the wording and the whole resistance that i don't get.

In the interval between the freezing point of water and 700 degrees C, a platinum resistance thermometer is used for interpolating the temperatures on the international scale the Celsius temperature Tc is given by a formula for resistance R with temperature
R = R0(1 + ATc +BTc^2) where A and B are constants determined by measurements at the ice point, the steam point of water, and the melting point of zinc (419.414 degrees C). (a) If R equals 10.000 ohms at the ice point, 13.946 ohms at the steam point, and 24.174 at the melting point of zinc, find R0, A, and B; (b) When immersed in a solution the length is 25.4 cm. What is the temperature of the solution.

now wtf?

 

[lightgrav]

Resistance is an electrical property of a device.
For metals, resistance increases (almost linearly)
Almost proportional to Temperature in Kelvin.
So expect B to be small.

What is Tc of the ice point? What, then, is Ro?
Do you know what temperature the "steam point" is?

 

[Andrew Mason]

For this one its a combination of the wording and the whole resistance that i don't get.

In the interval between the freezing point of water and 700 degrees C, a platinum resistance thermometer is used for interpolating the temperatures on the international scale the Celsius temperature Tc is given by a formula for resistance R with temperature
R = R0(1 + ATc +BTc^2) where A and B are constants determined by measurements at the ice point, the steam point of water, and the melting point of zinc (419.414 degrees C). (a) If R equals 10.000 ohms at the ice point, 13.946 ohms at the steam point, and 24.174 at the melting point of zinc, find R0, A, and B; (b) When immersed in a solution the length is 25.4 cm. What is the temperature of the solution.

now wtf?

I think you need more information in order to answer b).

AM

 

[ice87]

You see what I don't get is where all the numbers go, and what all the letters in the equation represent. I'm guessing for part A i need to setup 3 equations with 3 variables and R equalling 10.000, 13.946, and 24.174 ohms? and maybe with Tc equalling 0, 100, and 419.414 degrees C respectively?