Solve Thermodynamics Problem: 500g Copper Pipe & 4kg Water

[johnny_702]

I know its not meant to be a hard question but I just can't get my head around it. A 500g copper pipe is heated to 300 degrees C, if it was dropped into 4KG of water (approx gallon) at 25 degreesC what will be the final temp?

Change in internal energy (U)=heat or energy transferred to object from a higher temp body(Q) + work done on the object(W)

Q= s*m*change in T
s= specific heat, mass in g and change of temp(T)


Ive been at this all day I am afraid and still no hope. All forms that I try to work through seem to need the final temp before I can go anywhere.

attempted 1*400*25 for Q of water then 0.092*500*300 for Q of copper, and then subtracting these and working back to find the final temp. But I think this only applies if the water is heated from 25 to 300 which I doubt will happen.
thanks

 

[johnny_702]

Oh wait I think I just got it... 28.13 degrees C.

From saying that when they are in thermal equalibrium

(0.092*500)*(300-t(final))=(1*4000)*(t(final)-25)

13800-46t=4000t-100000

and working from there until 113800/4046=t

=28.13C


btw my bad for putting this in advanced physics, although it seemed it was for a while to me!