0.250 L 0.980 L 136.8 kPa expand work (J)

0.250 L 0.980 L 136.8 kPa expand work (J)

 

 

A fuel is burned in a cylinder equipped with a piston.

The initial volume of the cylinder is 0.250 L,

and the final volume is 0.980 L.

If the piston expands against a constant pressure of 136.8 kPa,

how much work (in J) is done?

 

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w = –PΔV

( 참고 https://ywpop.tistory.com/6336 )

 

= –(136800 Pa) (0.980 – 0.250 L)

= –99864 Pa•L

 

 

 

1 m3 = 1000 L 이므로,

(–99864 Pa•L) (1 m3 / 1000 L)

= –99.864 Pa•m3

 

 

 

1 Pa•m3 = 1 J 이므로,

–99.864 Pa•m3 = –99.864 J

 

 

 

 

또는

1 atm = 101325 Pa 이므로,

(136800 Pa) (1 atm / 101325 Pa)

= 1.350 atm

 

 

 

w = –PΔV

= –(1.350 atm) (0.980 – 0.250 L)

= –0.9855 atm•L

 

 

 

1 atm•L = 101.325 J 이므로,

(–0.9855 atm•L) (101.325 J / 1 atm•L)

= –99.856 J

 

 

 

답: –99.9 J

 

 

 

 

0.250 L 0.980 L 1.35 atm expand work (J)

A fuel is burned in a cylinder equipped with a piston.

The initial volume of the cylinder is 0.250 L,

and the final volume is 0.980 L.

If the piston expands against a constant pressure of 1.35 atm,

how much work (in J) is done?