Question

what is the net work output of paths ABCDA and ABDA

p (106 N/m2) А 2.6 2.0 B - D 1.0 0.6 с 0 0 1.0 4.0 V (10-3 m3)

Answer 1

since the work done for a cyclic process is given by enclosed area on pv diagram..

so first calculate work done for path ABCDA:

work done for path ABCDA is area enclosed by ABCDA;

area ABCDA= area of triangle ABD+area of triangle CDB;

area of ABD=0.5*(2.6-1)*(4-1)=2.4;

area of CDB=(0.5)*(2-0.6)*(4-1)=2.1;

so area enclosed by ABCDA =4.5 =work done in ABCDA ;

so area for the path ABCDA =4.5 J.

work done for path ABDA = area of traingle ABD;

as calculated above area of triangle ABD =2.4;

so work done in process ABDA =2.4 J.

hence work done for path ABCDA =4.5J,

work done for path ABDA =2.4J.