1. Ideal, monatomic gas goes around the cycle shown. Is this an engine or a fridge? A] engine B] fridge

2. What is the temperature at c? A] T a B] 2T a C] 3T a D] T a /3 E] cannot determine

3. T b =T a. A] p 0 V 0 B] - (2/3) p 0 V 0 C] - p 0 V 0 ln(3) D] - p 0 V 0 ln(1/3) E] cannot determine So T c = 3T a How much work does the gas do a-b? Use paper & pencil…

4. A] p 0 B] 2p 0 C] -2p 0 D] 3p 0 E] cannot determine T c = 3T a What is the pressure at b? W ab = - p 0 V 0 ln(3)

5. A] p 0 V 0 B] 3 p 0 (1/3) V 0 C] 3 p 0 (2/3) V 0 D] 0 E] cannot determine T c = 3T a What is the work done by the gas b-c? W ab = - p 0 V 0 ln(3)P b = 3P 0

6. A] p 0 V 0 B] 3 p 0 (1/3) V 0 C] 3 p 0 (2/3) V 0 D] 0 E] cannot determine T c = 3T a What is the work done by the gas c-a? W ab = - p 0 V 0 ln(3)P b = 3P 0 W bc = 3 p 0 (2/3) V 0

7. A] ab B] bc C] ca D] ab & bc E] bc & ca T c = 3T a Along which segments is heat added? W ab = - p 0 V 0 ln(3) P b = 3P 0 W bc = 2 p 0 V 0 W ca = 0

8. A] 2p 0 V 0 B] nC v T a C] nC p T a D] nC p 2T a E] nC p 3T a T c = 3T a Heat is added only along bc. How much heat is added? W ab = - p 0 V 0 ln(3) P b = 3P 0 W bc = 2 p 0 V 0 W ca = 0

9. T c = 3T a Now p 0 V 0 = nRT a. Let’s find the efficiency! W ab = - p 0 V 0 ln(3) P b = 3P 0 W bc = 2 p 0 V 0 W ca = 0 Q bc = nC p 2T a e= W/Q added