Find the equilbrium temperature

[WeiLoong]

Homework Statement

The thermal conductivites of the materials are 2k,k,4k respectively. Find the equilibrium temperature at X-Y Y-Zhttps://scontent-kul1-1.xx.fbcdn.net/hphotos-xpt1/v/t34.0-12/11950919_10204794824222021_851218095_n.jpg?oh=c15562066e063b2b164fbe7255d7d5d2&oe=55E9175C

Homework Equations

Thermal Conduction

The Attempt at a Solution

https://scontent-kul1-1.xx.fbcdn.net/hphotos-xft1/v/t34.0-12/11992166_10204794929704658_463646175_n.jpg?oh=b21361a78faa1427bd9de5c2a4d57a5c&oe=55EA2FB8
I am not sure whether i get it correct or not

 

[Titan97]

[Deleted]

 

[insightful]

Check your math!

 

[WeiLoong]

Check your math!

Hahaa i found my mistake it should be Qa/5 :D

 

[WeiLoong]

Take temperature at X-Y junction = T_a and temperature at Y-Z junction as T_b.
As you already know, the temperature difference $\Delta T=\frac{l}{kA}$
With this, you can find T_a and T_b.

I have no idea how to use this equation, Can you show me Ta using this formula? :D

 

[Titan97]

I am sorry. I meant $R=\frac{l}{kA}$. R is the resistance. Then use $H=\frac{\Delta T}{R}$. Its the same thing as you have done. I was in a hurry.