T7 - Phy sics 7B WS T7 ( rev. 3.0) Page 1 T-7. Entropy:...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
Physics 7B WS T7 (rev. 3.0) Page 1 T-7. Entropy: Other Topics Part 1: Entropy with Calorimetry Questions for discussion (Part 1) 1 . The melting point of lead is 327.5 o C. To melt one kilogram of lead at this temperature, you must add about 25,000 J of heat. When you do this, does the entropy of the lead change? (See if you can answer based on the qualitative idea of “order vs. disorder.”) 2 . In Discussion Question 1, if you said that the entropy of the system changes, then by how much? (Give a numerical answer.)
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Physics 7B WS T7 (rev. 3.0) Page 2 Problems (Part 1) 1 . A small lead block, of mass M and initial temperature 3T, is placed in contact with a large lead block, of mass 4M and initial temperature T. The system as a whole is isolated, so that no heat is lost to the surroundings. a) Will the final temperature of the two-block system be less than 2T, greater than 2T, or equal to 2T? b) Find the final temperature T f in terms of T. Was your answer to part (a) correct? c) Find the change in the entropy of the small block during this process. (Denote the specific heat of lead by c L .) Is your answer consistent with the Second Law? d) Next, find the change in entropy of the large block during this process. Is your answer consistent with the Second Law? e) Finally, find the change in entropy of the two- block system. Is your answer consistent with the Second Law? 2 . A lead block of mass M is at initial temperature T L . The block is placed within a thermally insulated canister of water. The water has mass m and is initially at temperature T W . If M = 12 kg, m = 75 g, and T
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 5

T7 - Phy sics 7B WS T7 ( rev. 3.0) Page 1 T-7. Entropy:...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online