Question

vital capacity (VC) = 4.5 L

inspiratory capacity (IC) = 3.3 L

calculate expiratory reserve volume (ERV) in liters

Answer 1

vital capacity is the maxium volume of air that a person can expire after a maximum inhalation

Vital capacity can be represented in formula as

Vital capacity (VC) = IRV +TV+ ERV

IRV (inspiratory residual volume) : it is the additional amount of air taken by the person during the forceful inspiration

TV(tidal volume ) : it is the normal volume of air inspired or expired during normal breathing

The sum of the IRV and TV is the Inspiratory capacity (IC).it is the amount of air inhaled during a deep breath

IC = (IRV +TV)

ERV (Expiratory residual volume : it is the additional amount of volume of exhaled during a forceful expiration

From this

VC (vital capacity ) = IC(inspiratory capacity ) + ERV(Expiratory residual volume)

Given that

VC = 4.5 L

IC = 3.3 L

So,

ERV = VC - IC = 4.5- 3.3 = 1.2L

The expiratory residual volume is 1.2 LITERS