Question 1

For a polyatomic gas, some internal energy may be stored as vibrational and/or rotational energy within the molecules. Describe what effect this will have on the adiabatic coefficient ê, which has the value 5/3 when only translational motion of molecules is allowed.

Accepted Answer

The answer of For a polyatomic gas, some internal energy...

Question 2

When a parcel of air is heated over a surface, it expands, thereby lowering its density relative to its surroundings, and experiences a buoyancy force, causing it to rise. Suppose that the ambient air is cold at the bottom and warmer at the top, giving rise to a "thermal inversion." What do you expect would happen to the heated parcel of air if this inversion were sufficiently strong, assuming the parcel expands adiabatically?

Accepted Answer

The answer of When a parcel of air is heated...

Question 3

Explain the difference between gauge pressure and absolute pressure.

Accepted Answer

The answer of Explain the difference between gauge pressure and...

Question 4

What characterizes the thermal energy of a system? Explain the difference between heat and thermal energy.

Accepted Answer

The answer of What characterizes the thermal energy of a...

Question 5

Describe what distinguishes thermal energy from other forms of energy.

Accepted Answer

The answer of Describe what distinguishes thermal energy from other...

Question 6

Two identical samples of gas at the same pressure and volume are compressed to the same final volume. If the first sample undergoes isothermal compression and the second sample adiabatic compression, compare the outcomes of the two processes.

Accepted Answer

The answer of Two identical samples of gas at the...

Question 7

Entropy of isolated systems undergoing irreversible processes increases and reaches a maximum when equilibrium is reached. What implications does this have for our universe?

Accepted Answer

The answer of Entropy of isolated systems undergoing irreversible processes...

Question 8

How did Joule's experiments lead to the formulation of the first law of thermodynamics?

Accepted Answer

The answer of How did Joule's experiments lead to the...

Question 9

Describe how you might use a waterfall to measure the equivalence of thermal and mechanical heat. What complications might make this experiment difficult to perform?

Accepted Answer

The answer of Describe how you might use a waterfall...

Question 10

Describe how you would improve the efficiency of a real engine operating between two reservoirs at temperatures T_high and T_low.

Accepted Answer

The answer of Describe how you would improve the efficiency...

Question 11

In the Carnot process, described in Section 9.6.2, heat is absorbed from a reservoir at a high temperature and heat is released to another reservoir at a lower temperature. Is it possible to run the cycle in reverse? If so, what effect would be achieved?

Accepted Answer

The answer of In the Carnot process, described in Section...

Question 12

Given some experimental data on pressure-versus-volume measurements, describe, in practical terms, how you would determine the work done by or on a system undergoing a cyclic process.

Accepted Answer

The answer of Given some experimental data on pressure-versus-volume measurements,...

Quiz 9: Thermal Physics