Physics 2A
Name_______________________
Conceptual Questions: Thermodynamics
Please circle the best answer
1. What is the lowest possible temperature in Kelvin units? ________________
2. Which has the gr eater amount of thermal energy
a. a cup of hot water b. an iceberg at the freezing point of water
3. Which of the f ollowing statements is a direct application of the Zeroth Law of Thermodynamics?
a. Block A has twice the temperature of Block B before they are brought into contact. Upon contact, thermal
energy flows from A to B.
b. A sample of gas within a cylinder with a piston is held at constant temperature and pressure while it is
allowed to expand. During this process, the gas absorbs heat from its surroundings.
c. The motor of a refrigerat or uses electric energy to remove heat from inside the refrigerator and transfer it to
the room.
d. A thermometer is calibrated by placing it in an ice water bath within an adiabatic cont ainer until the
thermometer is in thermal equilibrium with the ice water.
4. In one stage of a reversible process the temperature of an ideal gas remains constant as its volume is
decreased. Which of the following stateme nts regarding this situation is true?
a. The process is adiabatic
b. The pressure of the gas decreases.
c. Heat flows out of the gas into the surroundings.
d. The gas does positive work on its surroundi ngs.
5. A fixed amount of ideal gas is compressed adiabatically. Which entry in the table below correctly depicts the
sign of the work done, the change in the internal energy , and the heat exchanged with the environment?
work done change in internal energy heat exchanged
a. positive negative zero
b. negative zero positive
c. negative negative zero
d. positive positive zero
e. negative positive zero
6. Through a suitable apparatus, or by using suitable electric motor /generator syst ems, it is possible to construct a
machine that continuously takes in 5 units of energy, and puts out 7 units of energy.
a. True b. False
7. An isobaric process is represented on a pressure-volume graph by which one of the following:
a. a parabola b. a hyperbola c. a vertical line d. a horizontal line
8. For a ideal gas the ratio Cp/Cv is
a. always 1 b. always less than 1 c. always greater than 1.
9. Conservation of Energy is another name for
a. First Law of thermodynamics b. Second Law of thermodynamics
10. The disordering effect of heat
a. increases with increasing temperature b. decreases with increasing temperature
c. is constant d. increases with decreasing temperature
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