Thermodynamics, Statistical Physics, and Quantum Mechanics

THERMODYNAMICS AND STATISTICAL PHYSICS 101

So is indeed higherthan theaverage energy of theatoms:

c) From (b) weknow thateach atomleaving thecontainer takeswith it an

additionalenergy The flow rate of the atoms leaving

the container (from (a)) is

The energy flowrate from thecontainerbecomes

To keep the temperature of theatoms inside the container constant, we

have totransfersomeheat to it at the samerate:

Equating the flow rate to thedecrease of thenumber of atomsinsidegives

Solving this differentialequation, we canfind thechange innumberdensity:

is the time constant and is the initialnumberdensity. Therefore, the
heat flowrate is

4.1 5 Surface Contamination (Wisconsin-Madison)

The number ofmoleculesstriking a unitarea of the surfaceNduring the
time of theexperiment (seeProblem4.14) isgiven by

We then obtain