Heat Flowing Through A Sectioned Rod HELP

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A long insulated rod is connected between boiling water and an ice-water mixture, with a copper section and a steel section. The temperature at the copper-steel junction stabilizes at 65.0°C. The heat transfer equation is applied, using thermal conductivities of copper and steel. An initial calculation mistakenly squared the cross-sectional area, leading to an incorrect heat flow value. The error was corrected by converting the area from cm² to m², resulting in the proper calculation for heat flow in watts.
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Homework Statement



A long rod, insulated to prevent heat loss along its sides, is in perfect thermal contact with boiling water (at atmospheric pressure) at one end and with an ice-water mixture at the other. The rod consists of a 1.00 section of copper (with one end in the boiling water) joined end-to-end to a length of steel (with one end in the ice water). Both sections of the rod have cross-sectional areas of 4.00 . The temperature of the copper-steel junction is 65.0 after a steady state has been reached.
How much heat per second flows from the boiling water to the ice-water mixture?
Express your answer in watts

Homework Equations



H=kAdT/L
kcopper=385
ksteel=50.2

The Attempt at a Solution



Hcopper=Hsteel
Hcopper=385*0.04^2*35
= 21.56W
There's something wrong with this answer.. Can someone please help me?
Thank you!
 
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Hi tizzful,

In your expression you have squared 0.04 (which is (area/length) in meters); since they gave the area I don't believe that number should be squared.
 
Hello, yes I realized afterwards that its in cm squared and I need it in meters squared and therefore had to multiply it by 10^-4. Thank you
 
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