(a) A sample of gas expands from 370 cm 3 to 690 cm 3 while its pressure decreas

Question

(a) A sample of gas expands from 370 cm3 to 690 cm3 while its pressure decreases from 142 kPa to 117 kPa . How much work is done by the gas if its pressure changes with the volume according to path A shown in the P-V diagram in the Figure?

(b) How much work is done by the gas if its pressure changes with the volume according to path B shown in the P-V diagram in the Figure?

(c) How much work is done by the gas if its pressure changes with the volume according to path C shown in the P-V diagram in the Figure?

Explanation / Answer

V1=370 cm3=370 *10^-6, V2= 690 cm3=690*10^-6m^3

P1 =142 kPa, P2 = 117 kPa

A)W=area under A path

W= P1(V2-V1)=142 *10^3(690*10^-6-370 *10^-6)=45.44

B)W=area under A path

W=1/2*(V1-V2)*(P1-P2)+P2*(V1-V2)=1/2*(690*10^-6-370 *10^-6)*(142 *10^3-117*10^3) +117 *10^3(690*10^-6-370 *10^-6) =41.44J

C)P2(V2-V1) =117 *10^3(690*10^-6-370 *10^-6) =37.44J

Related Questions

Navigate

• Browse (All)
• Browse #
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.