Peoples Physics Book Version-3

http://www.ck12.org Chapter 19. Thermodynamics and Heat Engines

An ideal gas is a gas where the atoms are treated as point-particles and assumed to never collide or interact with each

other. If you haveNmolecules of such a gas at temperatureTand volumeV, the pressure can be calculated from

this formula. Note thatk= 1. 38 × 10 −^23 J/K; this is the ideal gas law

PV=nRT

Vis the volume,nis the number of moles;Ris the universal gas constant= 8 .315 J/K−n; this is the most useful
form of the gas law for thermodynamics.

ec= 1 −

Tc

Th

Efficiency of a Carnot (ideal) heat engine

whereTcandThare the temperatures of the hot and cold reservoirs, respectively.