Thermodynamics

Topics in this chapter

• Thermodynamic State and Gas Laws
• Heat, Work, and First Law
• Thermodynamic Processes
• Heat Capacity and Kinetic Theory
• Carnot Engines and Efficiency
• Refrigerators and Coefficient of Performance

Cheat sheet

Practice questions

1. Question 1Q-9DC54A

   During an adiabatic process, the pressure of a gas is found to be proportional to the cube of its absolute temperature ($P \propto T^3$). The ratio of specific heats $\gamma = \frac{C_p}{C_v}$ for the gas is:

   1. A.$3/2$
   2. B.$4/3$
   3. C.$5/3$
   4. D.$3/1$
   See the answer and solution
2. Question 2Q-5013E9

   Which of the following parameters does not characterize the thermodynamic state of matter?

   1. A.Temperature
   2. B.Pressure
   3. C.Work
   4. D.Volume
   See the answer and solution
3. Question 3Q-61E07F

   A Carnot engine has an efficiency of $50\%$ when its sink is at $300\text{ K}$. If the efficiency is to be increased to $70\%$ keeping the source temperature constant, the temperature of the sink must be decreased by:

   1. A.$120\text{ K}$
   2. B.$180\text{ K}$
   3. C.$60\text{ K}$
   4. D.$200\text{ K}$
   See the answer and solution
4. Question 4Q-E973F7

   First law of thermodynamics is a consequence of conservation of:

   1. A.Momentum
   2. B.Energy
   3. C.Mass
   4. D.Temperature
   See the answer and solution
5. Question 5Q-14A930

   An ideal gas expands according to the law $P V^2 = \text{constant}$. The molar heat capacity $C$ of the gas for this process is (where $R$ is the universal gas constant and $\gamma = C_p/C_v$):

   1. A.$C_v + \frac{R}{1-\gamma}$
   2. B.$C_v - \frac{R}{\gamma-1}$
   3. C.$C_v + R$
   4. D.$C_v - R$
   See the answer and solution