Your equations for TLC and VC aren't right. TLC=IRV+ERV+TV+RV and VC=IRV+TV+ERV so TLC=VC+RV.i'm confused b/w definitions. Kaplan says:
Residual volume = certain volume of air that can never be removed from healthy lungs during normal breathing process
then what is frc & erv ? I know frc = erv + rv...
Tlc = erv + vc
vc = tv + erv + irv
TV=Tidal Volume=Volume inspired or expired in a quiet breath.ah, ok, thought about it:
The functional residual capacity is the air left in after a regular breath (tidal volume). Then the residual volume is the air that left in after a forceful breath out, a "vital capacity" breath. That's why the frc includes the rv.