외부 압력이 101.3 kPa일 때 약 2.0 L만큼 팽창

호흡할 때 폐는 외부 압력이 101.3 kPa일 때 약 2.0 L만큼 팽창한다.

이때 일(J)은 얼마인가?

During a deep breath, our lungs expand about 2.0 L against an external pressure of 101.3 kPa. How much work is involved in this process (in J)?

> 101.325 kPa = 101.325×10^3 Pa

> 2.0 L = 2.0×10^(-3) m3

w = –PΔV

= –(101.325×10^3 Pa) (2.0×10^(-3) m3)

= –202.65 Pa•m3

= –202.65 J

답: -2.0×10^2 J

[키워드] lung 101.3 kPa 2.0 L expand

During a normal breath, our lungs expand about 0.50 L against an external pressure of 1.0 atm. How much work is involved in this process (in J)?

w = –PΔV

= –(1.0 atm) (0.50 L)

= –0.50 atm•L

1 atm•L = 101.325 J 이므로,

(–0.50 atm•L) (101.325 J / 1 atm•L)

= –50.6625 J

답: –51 J