Entropy Change of Universe: 6kg Block & Lake

AI Thread Summary
The discussion focuses on calculating the total entropy change of the universe when a 6kg block at 150°C is placed in a 0°C lake. The user has calculated the entropy change of the block to be -788 J/K but is uncertain about how to determine the entropy change of the lake due to the unknown mass. It is noted that while the heat transfer will be equal and opposite, the entropy changes will not necessarily be the same. The user seeks clarification on how to approach the calculation for the lake's entropy change. Understanding the relationship between heat transfer and entropy is crucial for solving this problem.
swain1
Messages
30
Reaction score
0

Homework Statement


Calculate the changes in total entropy of the universe as a result of the following processes:
(a) A block of mass 6kg and heat capacity of 300 J/K/kg at 150oC is placed in a lake at 0oC.

Homework Equations


The Attempt at a Solution


I think I have found the entropy change of the block as -788 J/K. I am not sure how to find the entropy change of the lake though as I don't know the mass.
Thanks for any help.
 
Physics news on Phys.org
The change should be equal but opposite. Heat is leaving the block and going into the water... What leave the block must enter the water...
 
yes the energy transfer will be the same but not the entropy.??
 
Thread 'Help with Time-Independent Perturbation Theory "Good" States Proof'

Thread 'Help with Time-Independent Perturbation Theory "Good" States Proof'

(Disclaimer: this is not a HW question. I am self-studying, and this felt like the type of question I've seen in this forum. If there is somewhere better for me to share this doubt, please let me know and I'll transfer it right away.) I am currently reviewing Chapter 7 of Introduction to QM by Griffiths. I have been stuck for an hour or so trying to understand the last paragraph of this proof (pls check the attached file). It claims that we can express Ψ_{γ}(0) as a linear combination of...
View full post »

Similar threads

Problem on entropy change and specific heat capacity
Replies
4
Views
4K
Work Check: Heat transfer between reservoir and small system
Replies
1
Views
2K
Calculating Entropy Change in a Lead-Lake System
Replies
4
Views
3K
A possible case of an irreversible process in which total entropy decreases
Replies
2
Views
2K
Chemistry No heat exchange with the surroundings in an irreversible expansion of an ideal gas?
Replies
4
Views
2K
Calculate Entropy Change for Process 1->3 in Au Block
Replies
2
Views
2K
Change in entropy of a capacitor
Replies
4
Views
8K
"Change in Entropy for Iron/Aluminum Equilibrium
Replies
2
Views
2K
Is Dropping a Metal Block into a Lake a Reversible Process in Thermodynamics?
Replies
1
Views
2K
Lake Hydrology Physics: Observing Shoreline Changes
Replies
4
Views
2K

Hot Threads

Recent Insights

Back
Top