1. problem 1.47. Think "1^st Law" here.
2. problem 1.61. Can you tell I like real-world applications here?
3. problem 3.10. This is exactly like the ΔS example I did in class with the steam condensing to water, then the water cooling down.
4. problem 4.3.
5. I want you to handle the real Diesel cycle on page 133 with real numbers. Let P₁=1.0 atm, V₁=0.50 L, T₁=300K. Let the compression ratio of 20:1 mean that V₂=(1/20)V₁. Then, the cutoff ratio is V₃/V₂, and accounts for what happens during injection of the gas/air mix and its subsequent ignition. Take the cutoff ratio to be 5, so that V₃=5V₂. As usual, for (mostly) diatomic air, let γ=1.4
   Note: In this problem, only the four steps shown in the cycle on page 133 are relevant. Label your curves in the following manner for clarity: Step (1) is the adiabat from V₁ to V₂; step (2) is the dP=0 line from V₂ to V₃; step (3) is the adiabat from V₃ to V₁; and step (4) is the dV=0 line at V₁.
   
   (a) Calculate the work done in each of the four steps in this cycle. Show your work for each of these calculations, even if W=0 for a step.
   
   (b) Assume C_V=(5/2)nR for an ideal gas that's not simply monatomic. Calculate the net heat gained or lost--include the correct sign--for the gas in each of the four steps in this cycle.
   
   (c) Calculate the net change in internal energy, ΔU, for each of the four steps in this cycle.
   
   Note: While I only assigned one real engine, they all behave the same: You calculate the same things for whatever cycle you're given, whether it's the diesel engine, an Otto engine, or a steam engine. Be able to calculate the work W, the heat Q and the change in internal energy ΔU for any such cycle.

That's all for homework #3.

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