Question

Can someone please check my work on this thermodynamics question? The answer came out to be a high number, not sure if I am correct.

Answer 1

@aum, any thoughts?

Answer 2

Yes, I am getting 22.7 degrees too. But I used the constants 387 and 4186 from your answer and I do not know if they are the correct numbers.

Answer 3

They were in our study guide, so I'm just going to use what my professor gave us.

Thank you very much for looking into this!

I'm curious though about the heat... does 1.22 Mega joules sound like too much heat to be transferred?

Answer 4

WolframAlpha gives values very close, but I will stick with his numbers since the TA will likely be using his as well.

Answer 5

"c" for copper is 387 but you have used "c" for water 4186 in the calculation for the second part.

Answer 6

Thank you VERY MUCH for that catch!

I've updated the work (see attached).

I'm not too familiar with thermodynamics, so I don't know if this is in the correct range... does 0.11 MJ sound reasonable?

Answer 7

And that last line should be -0.11 MJ

Answer 8

Well, "c" for water is 4186 Joules per Kg per degree centigrade.
That means it requires 4186 Joules to raise the temperature of 1 Kg of water by 1 degree Centigrade. Therefore, to raise 10 Kg of water by 1 degree will require 41860 J or 0.042 MJ. To raise 10 Kg of water by 2.7 degrees will require 41860 J or 0.042 MJ * 2.7 = 0.11 MJ which agrees with your answer.

Answer 9

Awesome!

And that's cool, I forgot that I can check my answer using kilo-calories.

I appreciate your help, thank you.

Answer 10

You are welcome.