Nevermind

[Theslowone]

I hate to post this but I can't figure it out, and I need to quick



An iron bar of length 67.7 cm and cross sectional area 23.7 square millimeters has a temperature difference of 56.0 degrees Celsius maintained between its ends. What is the rate, in watts, at which heat flows along the bar?

Sorry in a rush, don't know what happened to my post then i edited it, instead of editing the post it somehow made a new one.

 

[conjur]

Hate to post so you posted it twice?


😛

 

[chin311]

man, whered the other thread go, i posted the answer in that one 😉

 

[DrPizza]

H = dQ/dt = kA(difference in temp)/l
where H = rate of energy transfer, k is the thermal conductivity constant for the material, A is the cross sectional area, l is the length.

k is measured in W/mK, where K is the temperature difference in degrees Kelvin (which is the same as the temperature in degrees celsius)

All you have to do is plug in your numbers.... I don't know the thermal conductivity constant of iron off the top of my head... the book is across the room, and it's probably in your notes anyway... So, just plug the numbers in, including your k value for iron.

 

[dullard]

Originally posted by: DrPizza
H = dQ/dt = kA(difference in temp)/l
where H = rate of energy transfer, k is the thermal conductivity constant for the material, A is the cross sectional area, l is the length.

k is measured in W/mK, where K is the temperature difference in degrees Kelvin (which is the same as the temperature in degrees celsius)

All you have to do is plug in your numbers.... I don't know the thermal conductivity constant of iron off the top of my head... the book is across the room, and it's probably in your notes anyway... So, just plug the numbers in, including your k value for iron.

Yep the numbers are answered exactly in that way in his other post.

 

[Theslowone]

Thanks, sorry for the confusion, but I was rushing.
Guess I will slow down next time.

 

[DrPizza]

I saw the other post, but the question was blank. Hmm.
btw, thermal constant for iron is 80 watts per meter Kelvin