Sections
Key Equations

# Key Equations

 ideal gas law $PV=NkTPV=NkT$ first law of thermodynamics $ΔU=Q−WΔU=Q−W$ pressure $P=FAP=FA$ pressure–volume work $W=PΔVW=PΔV$
 change in entropy $ΔS=QTΔS=QT$
 thermal efficiency of a heat engine $Eff=WQhEff=WQh$ work output for a cyclical process $W=Qh−QcW=Qh−Qc$